Publications
Conference Papers:
1. V. Ahmadi, S. Noda, and A. Sasaki, "Two-Dimensional Static Simulation of HPT/LD Optoelectronic Integrated Device,� Japan Optics 92, paO2, 1992.
2. V. Ahmadi, S. Noda, and A. Sasaki, "Simulation of OEID's (I): Analysis and Optimum Design of HPT by 2-D Simulation,� the Japan Society of Applied Physics (JSAP), the 54th Autumn Meeting, P-E-10, 1993.
3. V. Ahmadi, S. Noda, and A. Sasaki, "Design of Very Sensitive HPT for OEID's by 2-D Simulation,� Tech. Report IEICE, ED93-131, CPM 93-102, PP. 67-70, 1993.
4. S. Noda, K. Shibata, V. Ahmadi, and A. Sasaki, "Functional Photonic Switching Device by Vertical and Direct Integration of Six HPT's and Two LD's,� OSA Proc. on Photonic in Switching, Vol. 16, USA, 1993.
5. V. Ahmadi, S. Noda, and A. Sasaki, "Two-Dimensional Simulation and New Structures of Heterojunction Phototransistor for OEID's ,� Topical Meeting of Int. Commission for Optics, 4p-31, 1994.
6. V. Ahmadi, S. Noda, and A. Sasaki, "Modeling and Analysis for Current-Voltage Characteristics of Integrated Devices of HPT and LD,� the Japan Society of Applied Physics (JSAP), the 41st Spring Meeting, a-G-2, 1994.
7. V. Ahmadi, S. Noda, and A. Sasaki, "Relative Intensity Noise (RIN) Analysis of OEID (II): Effect of Internal Feedback on RIN Characteristics,� the Japan Society of Applied Physics (JSAP), the 41st Spring Meeting, a-G-3, 1994.
8. V. Ahmadi, S. Noda, and A. Sasaki, "Fabrication and Analysis of an Optoelectronic Gate with Flip-Flop Function,� Iranian Annual Physics Conf., Abstract 289, 1996.
9. V. Ahmadi, S. Noda, and A. Sasaki, "Noise Characteristics of an Optoelectronic Integrated Light Amplifier,� Proc. 14th Iranian Conf. on Elect. Eng., Electronics, 52, 1996.
10. V. Ahmadi, "Computational Analysis of an Optical Amplifier Switch Integrated by HPT/LD,� Proc. 5th Iranian Conf. on Elect Eng. Electronics, 1997.
11. M. H. Sheikhi, V. Ahmadi, et al, �Modeling and Analysis of Dynamic Operation of an Integrated Optoelectronic Integrated Device Composed of HPT/LD,� 5th Conf. on Elect. Eng., Iran, Electronics Proceedings, 1997, (Persian).
12. M. Mohammadi, V. Ahmadi, �Fabrication and Characterization of a GaAs Solar Cell,� 4th Conf. on Condensed Matter, Iran, Proceedings, 1997 (Persian).
13. V. Ahmadi, M. H. Sheikhi, "Numerical Analysis for the Dynamic Response of an HPT/LD Optoelectronic Integrated Device,� Proc. 5th International Symp. On Advanced Material PP. 639-644, 1997.
14. V. Ahmadi, M. H. Sheikhi, "Numerical Analysis for Characteristics of a QW Structure Optoelectronic Integrated Device,� Proc. of IEEE Int. On Semiconductor for Electronics, ICSE98, 1998.
15. M. Oskoei, V. Ahmadi, �Optical Output Characteristics of a GaAs Laser Diode,� 5th Meeting of Optic Professionals,� 1998 (in Persian).
16. G. Abaiani, V. Ahmadi, et al, �Fabrication and Analysis of 1.3 �m Heterojunction LED and LD,� 6th Conf. on Elect. Eng., Iran, Electronics Proceedings, 1998 (Persian).
17. M. H. Sheikhi, V. Ahmadi, �Optimum Design of VCSEL for Very Short Optical Pulses,� 6th Conf. on Elect. Eng., Iran, Electronics Proceedings, 1998 (Persian).
18. H. S. Abedi, V. Ahmadi, et al, �Simulation of Index Guided Semiconductor Laser,� 7th Conf. on Elect. Eng., Iran, Electronics Proceedings, 1999 (Persian).
19. M. H. Sheikhi, V. Ahmadi, M. K. Morravej-Farshi," Optimum design of a Gain Switch Vertical Cavity Surface emitting Semiconductor Laser�, 7th Iranian Conference on Electrical Engineering 1999, Tehran-Iran. (in Persian).
20. V. Ahmadi, Quantum Optoelectronic Devices,� 1st Meeting of Optical Communication Devices Technology,� ITRC, Tehran, Iran, 1999 (in Persian).
21. N. Hatefi, V. Ahmadi, et al, �Simulation of Index Guided Semiconductor Laser,� 7th Conf. on Elect. Eng., Iran, Electronics Proceedings, 1999 (Persian).
22. F. Shahshahani, V. Ahmadi, et al, �Analysis for the Effects of Grating Structure on the Output Characteristics of DFB LD,� 1st Conf. on Applications of Physics and Nuclear Science in Medicine, Iran, Proceedings, 1999 (Persian).
23. A. Banoushi, V. Ahmadi, et al, �Analysis of a PIN-APD Characteristics,� 1st Conf. on Applications of Physics and Nuclear Science in Medicine, Iran, Proceedings, 1999 (Persian).
24. A. Banoushi, V. Ahmadi, �Modeling and Analysis for the Operation and Characteristics of a PIN Avalanche Photodiode,� 8th Conf. on Elect. Eng., Iran, Electronics Proceedings, 2000 (Persian).
25. M. H. Sheikhi, V. Ahmadi, �Analysis for Static and Dynamic Operation of a Quantum Well Optoelectronic Integrated Device with HPT/QW-LD Structure,� 8th Conf. on Elect. Eng., Iran, Electronics Proceedings, 2000 (Persian).
26. M. K. Moravvej, A. Zarifkar, V. Ahmadi, �Analysis of the Noise Intensity in Single Mode Laser Diode,� 8th Conf. on Elect. Eng., Iran, Electronics Proceedings, 2000 (Persian).
27. F. Shahshahani, V. Ahmadi, et al, �Analysis of the Line Width in DFB Laser Diode,� Iran Annual Physics Conf., Iran, Abstracts, 2000 (Persian).
28. F. Emami, V. Ahmadi, and M. K. Moravvej-Farshi, "Effects of Coupling Coefficient Variations on Threshold Parameters of DFB Laser,� The 8th Iranian Conf. on Elect. Eng., 2000.
29. M. K. Moravvej-Farshi, F. Emami, V. Ahmadi, " Coupling Coefficients for TE and TM modes for Coherent Fields in a Corrugated Five - Layer Waveguide,� The 8th Iranian Conf. on Elect. Eng., 2000.
30. V. Ahmadi, M. H. Sheikhi, M. K. Moravvej-Farshi, " Numerical Analysis for Static and Dynamic Characteristics of an Optical Amplifier - Switch Integrated Device.� International Conf. on Nanostructure Materials (Nano 2000), Japan, August 2000.
31. V. Ahmadi, M. H. Sheikhi, M. K. Moravvej-Farshi, " Analysis of Optical Gain and Rise-time of a QW-Structure Optoelectronic Integrated Device, 8th IEEE International Sym. on Electron Devices for Microwave and Optoelectronic Applications, DMO 2000, Scotland, 13-14 Nov. 2000.
32. V. Ahmadi, M. H. Sheikhi, M. K. Moravvej-Farshi, " Numerical Analysis for the Static and Dynamic Responses of an HPT/QW-LD Optoelectronic Integrated Device, the 12th International Conf. on Microelectronics, ICM 2000, Tehran, 2000.
33. M. H. Sheikhi, V. Ahmadi, M.K. Moravvej-Farshi, "A Physical Model for Characteristics of PIN/QW-LD Optoelectronic Integrated Device," 2001 IEEE Canadian Conference on Electrical and Computer Engineering, Canada, May 2001.
34. V. Ahmadi, M. H. Sheikhi, M. K. Moravvej-Farshi, "A Physical Model for Characteristics of," 9th Iranian Conference on Electrical Engineering (ICEE2001), Power and Water Institute of Technology, Tehran, Iran, May 2001.
35. M. Joodaki, G. Kompa, SMG Arshad, G. Kamucha, V. Ahmadi, and M. K. Moravvej-Farshi, "Application of Neural Networks for Distance Measurement in Pulsed Laser Radar (PLR),"3rd Topical Meeting on Optoelectronic Distance Displacement Measurement an Application (ODIMAP III), University of Pavia, Italy, Sept.2001.
36. M. Joodaki, G. Kompa, SMG Arshad, G. Kamucha, V. Ahmadi, and M. K. Moravvej-Farshi, "Neural Method for Near Distance Measurements with Overlapping of Reference and Reflected Pulses in Pulsed Laser Radar, "1st Conf Exhibit. on Microwaves, Radio Communication and Electromagnetic Compatibility, Messe Stuttgart, Germany, 8-10 May 2001.
37. K. Bayat, M. K. Moravvej-Farshi, V. Ahmadi, M. Zolfaghari, and M. F. Baroughi, "Design and Analysis of a Broadband Wavelength Polarization Independent Ti: LiNbO3 Directional Coupler," ST2001, Tehran, Iran, September 2001.
38. M. Joodaki, G. Kompa, SMG. Arshad, V. Ahmadi, M. K. Moravvej, �Neural Method for 2D High Contrast Imaging in PLR,� Proc. Of 31st European Microwave Conf., London, England, 2001.
39. A. Zarifkar, V. Ahmadi, and M. K. Moravvej-Farshi, �Analysis of Intensity Noise in Two-Mode Semiconductor Laser Diodes,� 10th Iranian Conference on Electrical Engineering (ICEE 2001), 2001.
40. F. Shahshahani, V. Ahmadi, K. Mirabbaszadeh, "New Structure of QWS-DFB Laser Diode for Reduction of SHB Effect,� 10th Iranian Conference on Electrical Engineering (ICEE 2002), University of Tabriz, Tabriz,
41. E. Mortazy, V. Ahmadi, and M. K. Moravvej-Farshi, �Circuit Modeling and Measurement of Noise for a Semiconductor Laser Diode,� 10th Iranian Conference on Electrical Engineering (ICEE 2002), University of Tabriz, Tabriz, Iran, May 2002.
42. M. H. Sheikhi, V. Ahmadi, M. K. Moravvej, T. Yao," A physical Modeling for Transient Response of Voltage-Tunable Optoelectronic Integrated functional Device�, 6th International Workshop on Expert Evaluation & Control of Compound Semiconductor Materials & Technology 2002, Budapest-Hungary.
43. M. H. Sheikhi, V. Ahmadi, M.K. Moravvej-Farshi, "Numerical Analysis for Characteristics of QW HPT/QW-LD Functional Optoelectronic Integrated Device,� 11th Iranian Conference on Electrical Engineering (ICEE 2003), Shiraz, 2003.
44. M. H. Sheikhi, V. Ahmadi, M.K. Moravvej-Farshi, T. Yao, "Fabrication and Characterization of a New Graded Structure GaAs/AlxGa1-xAs Metal-Semiconductor-Metal Photo detector,� Int'1 Symposium on Telecom. (IST2003), August, Isfahan, Iran, 2003.
45. G. Abaiyani, V. Ahmadi,"Computation and Analysis of Threshold Current for CW-Operation of Stripe Laser Diode Considering the Thermal Resistance of the Laser,� Int'1 Symposium on Telecom. (IST2003), August, Isfahan-Iran, 2003.
46. V. Ahmadi, F. Shahshahani, and E. Mortazy, "Analysis of RIN in DFB Semiconductor Laser Diodes Using Three Rate Equations Model,� Int'1 Symposium on Telecom. (IST2003), Isfahan, Iran, August, 2003.
47. E. Mortazy, V. Ahmadi, M. K. Moravvej, and A. Zarifkar, "Mode Partition, Mode Hopping and Phase Noise in a Two-Mode Semiconductor Laser,� International Conf. on Advanced Optoelectronics & Lasers, Alushta, Ukraine, September, 2003.
48. E. Mortazy, F. Shahshahani, V. Ahmadi, A. H. Tehranchi, M. K. Moravvej, �The Effect of Spatial Hole Burning on Relative Intensity Noise in DFB Laser Diodes,� Australians Conf. on Optics, Lasers and Spectroscopy, ACOLS 03, the Univ. of Melbourne 1-4 Dec. 2003.
49. M. Razzaghi, V. Ahmadi, A. Zarifkar, �Numerical Method for Dynamic Gain Analysis in Semiconductor Laser Amplifier,� Australians Conf. on Optics, Lasers and Spectroscopy, ACOLS 03, the Univ. of Melbourne 1-4 Dec. 2003.
50. B. Eftekhari, V. Ahmadi, �2-Dimensional Simulation and Analysis for Liquid Phase Epitaxy of III-V semiconductor Binary Compound Layers: InP and GaAs,� Int. Conf. on Physics, Proceedings, Tehran, Iran, 6-9 Jan. 2004.
51. M. Razzaghi, A. Zarifkar, M. Soroosh, V. Ahmadi, �Steady State Distributed Equivalent Circuit Model for Semiconductor Laser Amplifier,� Int. Conf. Optics & Photonics in Technology Frontier, ICO�04, Tokyo, Japan, 13-16 July, 2004.
52. M. Najafi, V. Ahmadi, G. Abaeiyani, �Experimental Study of Spontaneous Emission in Double Heterostructure InGaAsP/InP,� Iran Physics Conf., 23-26 Aug. 2004.
53. M. Soroosh, V. Ahmadi, � Calculation of Excess Noise in SAM-APD using MLP Neural Network,� 12th Iranian Conference on Electrical Engineering (ICEE 2004) Proc. Vol1, Mashhad, Iran, May 11-13, 2004 (in Persian).
54. E. Rahimian, V. Ahmadi, M. Noushiravani, � Gain Analysis of GaAs-AlxGa1-xAs Quantum Well Lasers with and without Valence Band Mixing for Different Quantum Well Thickness and Depths� 7th Condensed Matter Conf. Iran Tech. and Science University, Tehran, Iran, 25-26 Jan. 2004.
55. K. Abedi, M. H. Sheikhi, S. Golmohammadi, V. Ahmadi, � SPICE Model for Microwave Properties of Traveling-Wave Electro absorption Modulators,� IEEE International Conference on Semiconductor Electronics, ICSE2004, Kuala Lumpur, Malaysia, Dec. 7-9, 2004.
56. S. Golmohammadi, K. Abedi, V. Ahmadi, �Evanescent Optical Field Calculation with FDTD Method,� IEEE International Conference on Semiconductor Electronics, ICSE2004, Kuala Lumpur, Malaysia, Dec. 7-9, 2004.
57. M. Razzaghi, A. Zarifkar, V. Ahmadi, �Calculation of Dynamic Gain and Carrier Density in Semiconductor Laser Amplifier Using Transfer Matrix Method,� 13th ICEE2005, Proceeding Vol. 1, Zanjan, Iran, May 10-12, 2005 (in Persian).
58. S. Seifollapoor, H. Rasooli-Baghaei, V. Ahmadi, �Circuit Model for Analysis of Static Operation of VCSEL,� 13th ICEE2005, Proceeding Vol. 1, Zanjan, Iran, May 10-12, 2005 (in Persian).
59. M. H. Yavari, V. Ahmadi, A. Zarifkar, �Analysis of Optoelectronic Integrated 3-Segment DBR Tunable Semiconductor Laser Using Coupled Mode Method,� 13th ICEE2005, Proceeding Vol. 1, Zanjan, Iran, May 10-12, 2005 (in Persian).
60. M. H. Yavari, V. Ahmadi, A. Zarifkar, K. Abedi, �Simulation of Photon Density Distribution in Three Section DBR Tunable Laser Diode Based on the Transfer Matrix Method,� 2nd Int. Conf. on Advanced Optoelectronics and Lasers, CAOL 2005, Proceeding Vol.1, Yalta, Ukraine, 12-17 Sept. 2005.
61. E. Darabi, V. Ahmadi, K. Mirabbaszadeh, �Analysis for the Characteristics of a Voltage Tunable Functional Quantum Structure Optoelectronic Integrated Device,� 2nd Int. Conf. on Advanced Optoelectronics and Lasers, CAOL 2005, Proceeding Vol.2, Yalta, Ukraine, 12-17 Sept. 2005.
62. K. Abedi, V. Ahmadi, S. Golmohammadi, E. Darabi, M. H. Yavari, �Soliton Solution of Nonlinear Application to Bose-Einstein Condensation Using the FD Method,� CAOL 2005, Proceeding Vol.2, Yalta, Ukraine, 12-17 Sept. 2005.
63. M. Razzaghi, A. Zarifkar, B. Hadian, V. Ahmadi, �Calculation of the Spontaneous Emission Spatial Dependency in Semiconductor Laser Using Transmission Line Model,� 7th Int. Conf. on Laser and Fiber-Optic Networks Modeling, LFNM 2005, Yalta, Ukraine, 12-17 Sept. 2005.
64. M. H. Yavari, V. Ahmadi, F. Shahshahani, M. Razaghi, �Numerical analysis of three section distributed Bragg reflector tunable laser diode with modified oscillation condition based on the transfer matrix method,� Wireless and Optical Communications Networks, WOCN 2005, Second IFIP International Conference, UAE, Dubai, Page(s):187 � 191, 6-8 March 2005.
65. M. Razaghi, V. Ahmadi, K. Farahani, A. Zarifkar, M. Soroosh, M. K. Moravvej-Farshi, �Investigation of transient amplified spontaneous emission in semiconductor laser amplifier,� Wireless and Optical Communications Networks, WOCN 2005, Second IFIP International Conference, UAE, Dubai, Page(s):178 � 181, 6-8 March 2005.
66. V. Ahmadi, "Quantum Structure Semiconductor Optoelectronic Devices," Proc. of the 12th Conf. on Optics and Photonics, Shiraz, P. 33, 2005.
67. M. H. Yavari, V. Ahmadi, A. Zarifkar, �Analysis of Three-Section Distributed Bragg Reflector Tunable Laser Using Coupled Mode Theory ,� ICEE2005, Zanjan, 59-64, May, 2005 (in Persian).
68. M. Razzaghi, A. Zarifkar, V. Ahmadi, � Dynamic Analysis of Gain and Carrier Concentration in Laser Diode Using Transfer Matrix Method,� ICEE2005, Zanjan, 97-102, May, 2005 (in Persian).
69. S. Seifolah Poor, H. Rasooli, V. Ahmadi, � A Circuit Model for Static Analysis
Of VCSEL,� ICEE2005, Zanjan, 7-11, May, 2005 (in Persian).
70. F. Shahshahani, V. Ahmadi, "Analysis of the External Optical Feedback On the Stability of QWS-DFB Semiconductor Laser," Proc. Of the 12th Conf. on Optics and Photonics, Shiraz, PP. 239-243, 2005 (in Persian).
71. N. Bajdanzadeh, F. Shahshahani, H. Ghafoorifard, V. Ahmadi, " Analysis of the Non-uniform Grating Structure on the Frequency Response of QWS-DFB Semiconductor Laser," Proc. Of the 12th Conf. on Optics and Photonics, Shiraz, PP. 245-249, 2005 (in Persian).
72. K. Abedi, V. Ahmadi, M. K. Moravvej, M. H. Sheikhi, F. Gity, M. H. Yavari, " Circuit Simulation of Segmented Traveling Wave Electroabsorption Modulator Using HSPICE," ICOCN2005, Bangkok, 2005.
73. F. Gity, V. Ahmadi, M. Noushiravani, K. Abedi, A. Noorafkan, " Modeling and Numerical Analysis of Static and Dynamic Characteristics of GaAs/AlGaAs SQW High Power Diode Lasers Considering Thermal Effects," ICOCN2005, Bangkok, 2005.
74. A. Seyyed Faraji, V. Ahmadi, M. Noushravani, F. Gity, �Numerical Analysis of Filamentation in Conventional Double Heterostructure and Quantum Well High -Power Broad Area Laser DiodeArea Laser Diod, � ICSE-2006, Malaysia, Kuala Lampur, Dec. 2006.
75. E. Soudi, V. Ahmadi, �A Versatile HSPICE Electro-Opto-Thermal Circuit Model for Vertical-Cavity Surface-Emitting Lasers, � ICSE-2006, Malaysia, Kuala Lampur, Dec. 2006.
76. E. Soudi, V. Ahmadi, �Static Quasi 3D Thermal Simulation of Ion-Implanted Vertical-Cavity Surface-Emitting Lasers, � ICSE-2006, Malaysia, Kuala Lampur, Dec. 2006.
77. M. Gandomkar, V. Ahmadi, �Modeling and Analysis of a Piezo-Optic Microstructure, �International Conf. on Bio-Nanotechnology, ICBN2006, 2006.
78. E. Rahimian, V. Ahmadi, �Analysis of Gain in Compressive Strained GaAs/AlGaAs Laser Diodes, �Iranian Physics Conference, Shahrood, August 2006.
79. A. Seyyed Faraji, V. Ahmadi, M. Noushiravani, �Analysis of Filamentation Effect in High Power Single Quantum Well Laser Diodes, �13th Conf. on Optics and Photonics,� Tehran, Iran, Feb. 2006.
80. G. Abaeiani, V. Ahmadi, �Structural Design of Silicon Resonant Cavity Enhanced Waveguide Photodetectors, � 13th Conf. on Optics and Photonics,� Tehran, Iran, Feb. 2006.
81. V. Ahmadi, F. Shahshahani, �Effects of Nonuniform Gratings on RIN of DFB Semiconductor Lasers, � 13th Conf. on Optics and Photonics,� Tehran, Iran, Feb. 2006.
82. V. Ahmadi, E. Darabi, "Analysis for Dynamic Characteristics and Relative Intensity Noise of a New Polarization -Insensitive Quantum Well Optoelectronic Integrated Device," Proc. of 8th International Conf. on Transparent Optical Networks ICTON2006, PP. 151-156, 2006.
83. S. Seifolah Poor, V. Ahmadi, M. K. Moravvej, �Circuit Model for Analysis of Gain Spectrum and Power Saturation in Asymmetric MQW-SOA � 15Th ICEE2006, Proceeding, 109-114, 2006 (Persian).
84. A. Pishini, M. K. Moravvej-Farshi, Ebnali-Heidari and V. Ahmadi, �Femtosecond Soliton Generation and Comparison in Various Nonlinear Optical Loop Mirror (NOLM) Structures�, ICOCN 2007, Islamabad, Pakistan, 2007.
85. S. Masudy Panah, V. Ahmadi, �Effect of Scattering Loss on Gain and Noise of Double Carrier Multiplication APD�, ICOCN 2007, Islamabad, Pakistan, 2007.
86. V. Ahmadi, K. Abedi, E. Darabi, �New Asymmetric Quantum Well Traveling-Wave Electroabsorption Modulator with Very Low Insertion Loss and High Extinction Ratio�, Proc. of 9th International Conf. on Transparent Optical Networks ICTON2007, PP. 251-256, 2007.
87. G. Abaeiani, V. Ahmadi, K. Sghafi, � New Asymmetric Quantum Well Traveling-Wave Electroabsorption Modulator with Very Low Insertion Loss and High Extinction Ratio�, Proc. of 9th International Conf. on Transparent Optical Networks ICTON2007, PP. 251-256, 2007.
88. D. Ghodsi, V. Ahmadi, E. Rajaei, and M. Yavari �Study the Effect of Phonon Bottle-neck and Inhomogeneous Broadening on the Self-assembled InGaAs/GaAs Quantum Dot Laser Operation�, 15th Spring Physics Conference, IPM, Tehran, Iran, 2008 (Persian).
89. M. Eskandari, V. Ahmadi, �Fabrication and Surveying Solvent Effect on the Morphology and Optic Property of ZnO Nanorod�, 16th Iranian Conf. on Electrical Engineering (ICEE2008), Tehran, Iran, 2008 (Persian).
90. G. Abaeiani, V. Ahmadi, K. Saghafi, �Microring Waveguide Infrared Photodetectors for WDM Optical Interconnection�, 16th Iranian Conf. on Electrical Engineering (ICEE2008), Tehran, Iran, 2008.
91. M. Yavari, V. Ahmadi, �Circuit Model of Carrier and Photon Dynamics in Semiconductor Self Assembled Quantum Dot Laser�, 16th Iranian Conf. on Electrical Engineering (ICEE2008), Tehran, Iran, 2008.
92. E. Sooudi, V. Ahmadi, E. Darabi, �Analysis of the Chirp Parameter for Strained Symmetric Coupled Quantum Well Electroabsorption Modulator�, 16th Iranian Conf. on Electrical Engineering (ICEE2008), Tehran, Iran, 2008.
93. M. Zavvari, V. Ahmadi, A. Zarifkar, �Numerical Analysis of Transverse Modes for a Quantum Well vertical-Cavity Surface-Emitting Laser with Gain-Guided Structure�, 16th Iranian Conf. on Electrical Engineering (ICEE2008), Tehran, Iran, 2008.
94. M. Aghaeepour, V. Ahmadi, E. Darabi, �Static and Dynamic Transverse-Mode Control of Vertical-Cavity Surface-Emitting Lasers Using an Improved Quantum Gain Model�, 16th Iranian Conf. on Electrical Engineering (ICEE2008), Tehran, Iran, 2008.
95. D. Ghodsi, V. Ahmadi, et al. �Analysis of Static-Characteristics of Self-Assembled InGaAs/GaAs Quantum Dot Lasers�, 14th Annual IASBS Meeting on Condensed Matter Physics, Institute for Advanced Studies in Basic Science (IASBS), Zanjan, Iran, 2008 (Persian).
96. D. Ghodsi, V. Ahmadi, �Static and Dynamic Characteristics Simulation of Self-Assembled InGaAs/GaAs Quantum Dot Lasers�, OSA�s 92 RD ANNUAL MEETING: Frontiers in Optics (FIO)/Laser Science XXIV (LS), New York, USA, 2008 (accepted).
97. D. Ghodsi, V. Ahmadi, and E. Rajaei, �Analysis of output characteristics and gain of self-assembled InGaAs/GaAs quantum dot lasers and the effects of carrier relaxation dynamics�, 13th Annual Physics Conference of Iran, Kashan University, Kashan, Iran, 2008 (accepted).
98. D. Ghodsi, V. Ahmadi, and E. Rajaei, �Study of Phonon Bottleneck and Inhomogenous Broadening on InGaAs/GaAs Self Assembled Quantum Dot laser Operation�, 15th Spring Physics Conference, Physics Institute, IPM, Tehran, Iran, 2008.
99. A. Chaman Motlagh, V. Ahmadi, Z. Ghassemlooy and K. Abedi,, �The Effect of Atmospheric Turbulence on the Performance of the Free Space Optical Communications�, 6th International Symposium on Communication Systems, Networks and Digital Systems (CSNDSP08), Graz, Austria, 2008.
100. K. Abedi, V. Ahmadi, M. K. Moravvej-farshi and A. Chaman Motlagh, �Full-vectorial Finite Difference for Optical Analysis of Traveling Wave Electroabsorption Modulators�, 6th International Symposium on Communication Systems, Networks and Digital Systems (CSNDSP08), Graz, Austria, 2008.
101. M. Razaghi, V. Ahmadi and M. J. Connelly, �Investigation of cross-phase modulation effect on picosecond optical pulses in a semiconductor optical amplifier using finite-difference beam propagation method�, Photonics Ireland 2007, Salthill, Ireland, 2007.
102. M. Eskandari, V. Ahmadi, S. H. Ahmadi and F. Ghorab, �Raman Spectroscopy in Aluminum-Doped Zinc Oxide Nanorods� 2nd IEEE Int. Nanoelectronics Conference (INEC 2008), Shanghai, China, 2008.
103. S. Masudu-Panah, V. Ahmadi, and F. Ghorab, �Effect of Temperature Variation on the Gain and Noise of Double Carrier Multiplication APDs�, 2nd IEEE Int. Nanoelectronics Conference (INEC 2008), Shanghai, China, 2008.
104. S. Masudy-Panah, V. Ahmadi, �Effect of Multiplication Region Mole Fraction on Characteristics of APDs�, 14th Conference on Optics and Photonics, Rafsanjan, January 2008.
105. H. Zare, V. Ahmadi, S. H. Ahmadi and M. Naderi, �Analysis of Structural and Optical Characteristics of ZnO/SiO2 Nanocomposite Prepared by Sol-Gel�, 14th Conference on Optics and Photonics, Rafsanjan, January 2008b (Persian).
106. H. Zare, V. Ahmadi, S. H. Ahmadi and M. Naderi, �Synthesis of Nanoparticles of ZnO and ZnO:MgO and Analysis of their Structural and Optical Characteristics�, 14th Conference on Optics and Photonics, Rafsanjan, January 2008 (Persian).
107. V. Ahmadi and S. Masudy-Panah, �Temperature variation effect on dynamic characteristics of GaAs avalanche photodiodes�, 10th Anniversary International Conference on Transparent Optical Networks, ICTON 2008, Greece, 2008.
108. V. Ahmadi and M. H. Yavari, �Analysis of carrier and photon dynamic effects on the modulation behavior of self assembled quantum dot laser�, 10th Anniversary International Conference on Transparent Optical Networks, ICTON 2008, Greece, 2008. H. Zare Bidaki,
109. H. Zare Bidaki, V. Ahmadi, S. Ahmadi, �Synthesizing nanoparticles of ZnO:SiO2 nanocomposite by using sol-gel technique�, The 2nd Int. Conf. on Nanotechnology 2008 (ICN08), Abu Dhabi, UAE, 2008.
110. H. Zare Bidaki, V. Ahmadi, S. Ahmadi, �Characterization and synthesis of ZnO:SiO2 nanocomposite using ZnO nanoparticles�, The 2nd Int. Conf. on Nanotechnology 2008 (ICN08), Abu Dhabi, UAE, 2008.
111. M. Fattah, V. Ahmadi, S. Ahmadi, �Preparation and Characterization of Nanostructured Tungsten Oxide Electrochromic Layer by Sol-Gel Method�, The 2nd Int. Conf. on Nanotechnology 2008 (ICN08), Abu Dhabi, UAE, 2008.
112. M. Aghaeepour, V. Ahmadi, E. Darabi, �The Effect of Nonlinear Gain on the Quantum Well VCSEL Characteristics�, The 2nd Int. Conf. on Nanotechnology 2008 (ICN08), Abu Dhabi, UAE, 2008.
113. A. Mirdrikvandi, V. Ahmadi, �Analysis and design of near room temperature InAs/GaAs QDIP using FDM for far infrared 8-12 �M window�, The 2nd Int. Conf. on Nanotechnology 2008 (ICN08), Abu Dhabi, UAE, 2008.
114. M. Skandari, V. Ahmadi, S. Ahmadi, �Synthesis and characterization of ZnO nanorods and nanowires using PVP as capping�, The 2nd Int. Conf. on Nanotechnology 2008 (ICN08), Abu Dhabi, UAE, 2008.
115. G. Tahmasebipour, V. Ahmadi, Y. Hojjat and A. Abdullah, �Fabrication of STM W Nanotip by Electrochemical Etching Method�, The 2nd Int. Conf. on Nanotechnology 2008 (ICN08), Abu Dhabi, UAE, 2008.
116. M. Razaghi, V. Ahmadi and M. J. Connelly, G. Madanifar, �Investigation of Bidirectional Femtosecond Pulses in SOAs Using a Modified Nonlinear Schr�dinger Equation and Improved Finite Difference Method�, International Conf. on Fiber Optics and Photonics, Photonics 2008, New Delhi, India, 2008.
117. M. Dehghan, V. Ahmadi and E. Darabi, �Investigation and Analysis of Time Response in Geiger Mode Avalanche Photodiode�, ICOP 2009, Isfahan, Iran, 2009.
118. H. Zare, V. Ahmadi and M. Zangi, �Synthesis and Characterization of ZnO-Silica Nanocomposite Using SBA-3 Meso-Porous� ICOP 2009, Isfahan, Iran, 2009.
119. A. Chaman Motlagh, V. Ahmadi and Z. Ghassemlooy, �Performance of Free Space Optical Communication Using M-Array Receivers at Atmospheric Condition�, 17h Iranian Conf. on Electrical Engineering (ICEE2009) Tehran, Iran, 2009.
120. A. Dehgan and V. Ahmadi, �Modeling and Analysis of Resonant Cavity Enhanced-Separated Absorption Graded Charge Multiplication Photodetector", 17h Iranian Conf. on Electrical Engineering (ICEE2009) Tehran, Iran, 2009.
121. A. Mir, V. Ahmadi and M. Gandomkar, �A New Structure Design for Low Dark
Current QDIP�, 17h Iranian Conf. on Electrical Engineering (ICEE2009) Tehran, Iran, 2009.
122. M. H. Yavari and V. Ahmadi, �Numerical Analysis of Optical Gain and Lasing Spectra of InGaAs-GaAs Self Assembled Quantum Dot Lasers�, 17h Iranian Conf. on Electrical Engineering (ICEE2009) Tehran, Iran, 2009.
123. P. Rafiee and V. Ahmadi, �Design and Analysis of a High Sensitive 2-Degree of Freedom Piezoresistive Accelerometer�, 17h Iranian Conf. on Electrical Engineering (ICEE2009) Tehran, Iran, 2009.
124. A. Ghadimi, A. Ahmadpour, and A. Ahadpour and V. Ahmadi, "Modeling and Operation Analysis of a Three-terminal Heterojunction Bipolar Phototransistor", 6th International Conference (ECTI_CON2009), Pattaya, Chonburi, Thailand, May 6th - 9th, 2009.
Reviewed Journal Papers:
1. V. Ahmadi, S. Noda, and A. Sasaki, "Optical Multi stable Set-Reset Functional Integrated Device Composed of Six Heterojunction Phototransistors and Two Laser Diodes,� Solid State Electronic, Vol. 38, No.3, PP. 551-558, 1995.
2. V. Ahmadi, S. Noda, and A. Sasaki, "2-D Simulation and New Structure of HPT for Integrated Device in Optoelectronic Integrated Devices,� Optical Review, Vol. 2, No. 2, PP. 120-122, 1995.
3. V. Ahmadi, S. Noda, and A. Sasaki, "Analysis for Relative Intensity Noise of Optoelectronic Integrated Device by Heterojunction Phototransistor and Laser Diode,� Solid State Electronics, Vol. 41, No. 3, PP. 465-471, 1997.
4. V. Ahmadi, H.H. Sheikhi, M.K. Moravvej, "Numerical Analysis for Static and Dynamic characteristics of an Optical Amplifier-Switch,� Scripta Materialia, Vol. 44, No. 59, PP. 1207-1212, 2001.
5. M. Joodaki, G. Kompa, V. Ahmadi, M. K. Moravvej," Using Neural Network for High Resolution Distance Measurement in PLR." SPIE Proc., Vol. 4471, PP. 180-189, 2001.
6. M. K. Moravvej, A. Zarifkar, V. Ahmadi, �Analysis of the Noise in Single Mode Semiconductor Laser Diodes,� Amir-Kabir Scientific and Research J., Vol. 48, PP. 449-437, 2001(in Persian).
7. A. Banoushi, V. Ahmadi, S. Setayeshi, "An Analytical Approach to Study the Effect of Carrier Velocities on the Gain and Break down Voltage of APD,� IEEE J. of Light Wave Tech., Vol. 20, No. 4, PP. 696-699, 2002.
8. F. Shahshahani, V. Ahmadi, K. Mirabbaszadeh, "Concave Tapered Grating Design of DFB Laser at High Power Operation for Reduced Spatial Hole-Burning Effect,� Material Science Engineering B, Vol. B96, PP. 1-7, 2002.
9. M. H. Sheikhi, V. Ahmadi, M. K. Moravvej, "A Physical Model for Characteristics of an Optical Amplifier-switch Integrated Device,� Iranian J. of Science & Technology, Trans. B, Vol. 26, No. B4, 665- 673, 2002.
10. E. Mortazy, V. Ahmadi, M. K. Moravvej, "An Integrated Equivalent Circuit Model for Relative Intensity Noise and Frequency Noise Spectrum of a Multimode Semiconductor Laser ,� IEEE J. Quantum Electronics Vol. 38, No. 10, PP. 1366-1371, 2002.
11. F. Emami, M. K. Moravvej, V. Ahmadi, �Analysis of Grating Dimensions on Ridge Waveguide DFB-LD Characteristics,� Int. Journal of Engineering, University of Science & Eng., Vol. 13, No. 3, PP. 21-32, 2002 (in Persian).
12. A. Banoushi, V. Ahmadi, S. Setayeshi, "Frequency and Temporal Response of an SAM-APD,� Amir-Kabir Scientific and Research J., Vol. 53, PP. 122-130, 2002 (in Persian).
13. F. Shahshahani, V. Ahmadi, K. Mirabbaszadeh, "The Effects of Grating Phase and Facets Reflections on the Optical Field Inside Semiconductor QWS-DFB Laser Diode,� Modares Technical and Engineering Scientific Research J., No. 7, PP. 1-12, 2002 (in Persian).
14. V. Ahmadi, E. Mortazy, A. Zarifkar, M. K. Moravvej, �Measurement and Analysis of Intensity and Phase Noise in Telecommunication Multimode Laser Diodes,� Amir-Kabir Scientific and Research J., Vol. 53, PP. 249-258, 2002 (in Persian).
15. K. Saghafi, M. K. Moravvej, V. Ahmadi, �An Improved Monte Carlo Method for Electron Transport in Low Electric Field for Degenerate Semiconductors,� Daneshvar, Scientific-Research Journal, PP. 1-10, March 2003 (in Persian).
16. E. Mortazy, V. Ahmadi, M. K. Moravvej, "Circuit Modeling and Measurement of Noise for Semiconductor Laser Diode,� J. of Faculty of Engineering, Tabriz University, Vol. 29, No. 1, 2003.
17. K. Saghafi, M. K. Moravvej, V. Ahmadi, �?-Doped LDD MESFET with Heterostructure,� Modares Technical and Engineering Scientific Research J., Autumn, 99-103, 2003 (in Persian).
18. A. Zarifkar, M. K. Moravvej, V. Ahmadi, �Numerical Analysis for Side Mode Effects on the Noise Characteristics of Semiconductor Laser Diodes,� Int. Journal of Engineering, University of Science & Eng., Vol. 14, No. 1, PP. 23-44, 2003 (in Persian).
19. M. H. Sheikhi, V. Ahmadi, M, K. Moravvej, �Physical Modeling for Transient Response of Voltage-Tunable Optoelectronic Integrated Functional Device,� Physica Status Solidi (C), Vol. 0, No. 3, 961- 966, 2003.
20. E. Mortazy, F. Shahshahani, V. Ahmadi, A. Tehranchi, M. K. Moravvej, " The Effect of Grating Structure on Relative Intensity Noise in DFB Laser Diode", SPIE Proc. Vol. 5468, PP. 154-164, 2004.
21. K. Saghafi, M. K. Moravvej, V. Ahmadi, "The Effects of the Semiconductor Properties and MESFET Structure on Electron Transport Characteristics-Monte Carlo Analysis", Modares Technical and Engineering Scientific Research J., No. 22, PP. 11-22, 2005.
22. E. Darabi, V. Ahmadi, K. Mirabbaszadeh, " Numerical Analysis of an Optoelectronic Integrated Device Composed of Coupled Periodic MQW Phototransistor and Strained-QW Laser Diode", Solid State Electronics, Vol. 50, PP. 473-479, 2006.
23. G. Abaeiani, V. Ahmadi, K. Saghafi, " Design and Analysis of Resonant Cavity Enhanced-Waveguide Photodetector Microwave Photonic Applications," IEEE Photonics Technology Letter, Vol. 18, No. 15, PP. 1597-1599, 2006.
24. M. Razaghi, V. Ahmadi, and A. Zarifkar, �Dynamic Analysis of Semiconductor Laser Amplifier Using Transfer Matrix Method�, Modarres Technical and Engineering, No. 26, 2007.
25. K. Abedi, V. Ahmadi, E. Darabi, M. K. Moravvej, and M. H. Sheikhi," Design of a Novel Periodic Asymmetric Intra-Step-Barrier Coupled Double Strained Quantum Well Electroabsorption Modulator at 1.55 ?m", Solid-State Electronics, Vol. 52, No. 2, pp. 312-322, 2008.
26. N. Bajdanzadeh, V. Ahmadi, F. Shashahani, and H. Ghafoorifard" Dynamic Response of QWS-DFB Lasers with Convex Tapered Grating Structure and Non-Zero Facet Reflection", Solid-State Electronics, Vol. 52, No. 2, pp. 221-226, 2008..
27. F. Shashahani and V. Ahmadi, �Analysis of Relative Intensity Noise in Tapered Grating QWS-DFB Laser Diodes by using Three Rate Equations Model�, Solid-State Electronics, Vol. 52, No. 2, pp. 857-862, 2008..
28. M. Dehghan and V. Ahmadi, �Opto-Electro-Thermal Model for MQW Laser Including Self-Heating and Chirping Effects�, IJCSNS International Journal of Computer Science and Network Security, Vol. 8, No. 3, pp. 88-91, 2008.
29. W.O. Popoola and Z. Ghassemlooy and V. Ahmadi, �Performance of Sub-carrier modulated Free-Space Optical Communication Link in Negative Exponential Atmospheric Turbulence Environment�, Int. J. Autonomous and Adaptive Communications Systems, Vol. 1, No. 3, pp. 342-355, 2008.
30. S. Masudy-Panah and V. Ahmadi, �A Closed Form Analytic Model to Study the Characteristics of Avalanche Photodiodes�, J. of Modern Optics, Vol. 56, No. 1, pp. 67-72, 2009.
31. M. H. Yavari and V. Ahmadi, �Analysis of Three Section Distributed Bragg Reflector Tunable Laser Diode Based on the Transfer Matrix Method�, Modares Technical and Engineering, No. 34, pp. 1-12, 2009 (in Persian).
32. W. Popoola, Z. Ghassemlooy, V. Ahmadi and E. Leitgeb, �MIMO Free-Space Optical Communication Employing Subcarrier Intensity Modulation in Atmospheric Turbulence Channels�, IEEE Trans. on Communications (to be published).
33. Gh. Tahmasebipour, Y. Hojjat, V. Ahmadi, A. Abdullah, �Optimization of STM/FIM nanotips aspect ratio based on the Taghuchi method�, Int. J. of Advance Manufacturing Technology, Vol. 44, pp. 80-90, 2009.
34. H. Aghajanpour, V. Ahmadi and M Razaghi, �Ultra-short optical pulse shaping using semiconductor optical amplifier�, Optics & Laser Technology, Vol. 41, No. 5, pp. 654-658, 2009.
35. M. Razaghi, V. Ahmadi, and M. Connelly, �Improved Finite-Difference Time Dependent Beam Propagation Scheme for Analyzing Counter Picosecond Pulse Propagation in Semiconductor Optical Amplifier�, IEEE J. of Lightwave Technology, Vol. 27, No. 15, pp. 3162-3174, 2009.
36. M. H. Yavari and V. Ahmadi, �Circuit Level Implementation of Semiconductor Self Assembled Quantum Dot Laser�, IEEE J. of Selected Topics in Quantum Electronics, Vol. 15, No. 3, pp. 774-779, 2009.
37. Gh. Tahmasebipour, Y. Hojjat, V. Ahmadi, A. Abullah, �Effect of Fabrication Process Parameters on the Apex-radius of STM Tungsten Nanotip�, Scanning, Vol. 31, pp. 65-74, 2009.
38. E. Darabi, V. Ahmadi, " Design and Numerical Analysis of a Polarization-Insensitive Quantum Well Optoelectronic Integrated Amplifier-Switch", Solid State Electronics, Vol. 53, No. 3, pp. 383-388, 2009.
39. M. Eskandari, V. Ahmadi and Sh. Ahmadi, �Low Temperature Synthesis of ZnO Nanorods by Using PVP and Their Characterization�, Physica B: Condensed Matter, Vol. 404, No. 14-15, pp. 1924-1928, 2009.
40. Gh. Tahmasebipour, V. Ahmadi, Y. Hojjat and A. Abullah, �FABRICATION OF STM TUNGSTEN NANOTIP BY ELECTROCHEMICAL ETCHING METHOD�, International Journal of Nanoscience (IJN), Vol. 8, No. 3, pp. 305-310, 2009.
41. A. Mir and V. Ahmadi, " Design and analysis of a new structure of InAs/GaAs QDIP for 8-12 m infrared windows with low dark current", Journal of Modern Optics, Vol. 56, No. 15, pp. 1704�1712, 2009.
42. A. Chaman-Motlagh, V. Ahmadi and Z. Ghassemlooy, "A modified model of the atmospheric effects on the performance of FSO links employing single and multiple receivers", Journal of Modern Optics, Vol. 57, No. 1, pp. 37-42, 2010.
43. M. Eskandari, V. Ahmadi and Sh. Ahmadi, �Growth of Al-doped ZnO nanorod arrays on the substrate at low temperature�, Physica E: Low-dimensional Systems and Nanostructures, (to be published-2010).
