Full-length Papers (*: Invited)
[1] * T. Numai, “Progress in
semiconductor tunable wavelength filters,” (Invited Paper, in Japanese) Trans.
IEICE, vol.J73-C-I, No.5, pp.347-353 (1990).
[2] S.
Suzuki, M. Nishio, T. Numai, M. Fujiwara, M. Itoh, S. Murata, and N. Shimosaka,
“A photonic wavelength-division switching system using tunable laser diode
filters,” IEEE/OSA J. Lightwave
Technol., vol.8, No.5, pp.660-666 (1990).
[3] * T. Numai,
“Semiconductor wavelength tunable optical filters,” (Invited Paper) Int. J. Optoelectron., vol.6, No.3, pp.239-252 (1991).
[4] T.
Numai, “1.5 μm semiconductor wavelength tunable
optical filter using a λ/4-shifted passive waveguide grating resonator,” Jpn. J. Appl. Phys., Part 1, vol.30, No.10, pp.2519-2525
(1991).
[5] K.
Kasahara, T. Numai, H. Kosaka, I. Ogura, K. Kurihara, and M. Sugimoto, “Vertical to surface
transmission electro-photonic device (VSTEP) and its application to optical
interconnection and information processing,” IEICE Trans. Electron., vol.E75-C,
No.1, pp.70-80 (1992).
[6] T.
Numai, “1.5-μm wavelength tunable phase-shift-controlled distributed feedback
laser,” IEEE/OSA J. Lightwave Technol., vol.10, No.2, pp.199-205 (1992).
[7] M.
Sugimoto, T. Numai, I. Ogura, H. Kosaka, K. Kurihara, and K. Kasahara, “Vertical-to-surface
transmission electro-photonic device with a pnpn
structure and vertical cavity,” Optical and Quantum Electron., vol.24, No.2,
pp.S121-S132 (1992).
[8] T.
Numai, “1.5 μm phase-controlled distributed feedback
wavelength tunable optical filter, “IEEE J. Quantum Electron., vol.28, No.6,
pp.1508-1512 (1992).
[9] T. Numai,
“1.5 μm phase-shift-controlled distributed feedback
wavelength tunable optical filter,” IEEE J. Quantum Electron., vol.28, No.6,
pp.1513-1519 (1992).
[10] T. Numai, “1.5 μm two-section Fabry-Perot wavelength tunable optical
filter,” IEEE/OSA J. Lightwave Technol., vol.10, No.11, pp.1590-1596 (1992).
[11] M. Nishio, K. Takagi, S. Suzuki, I. Ogura, T. Numai, K.
Kasahara, and K. Kaede, “A photonic ATM switch using
vertical to surface transmission electro-photonic devices (VSTEPs),” (in Japanese) Trans. IEICE,
vol.J75-C-I, No.5, pp.320-329 (1992).
[12] Y. Yamanaka, T.
Numai, K. Yoshihara, I. Ogura, H. Kosaka, K. Kurihara, M. Sugimoto, K. Kasahara, and K. Kubota,
“Vertical to surface transmission electro-photonic device and its application
for optical interconnection,” (in Japanese) Trans. IEICE, vol.J75-C-I, No.5,
pp.330-339 (1992).
[13] Y. Yamanaka, K.
Yoshihara, I. Ogura, T. Numai, K. Kasahara, and Y. Ono, “Free-space optical bus using cascaded
vertical-to-surface transmission electrophotonic
devices,” Appl. Opt., vol.31, No.23, pp.4676-4681 (1992).
[14] K. Kurihara, T. Numai, I. Ogura, A. Yasuda, M. Sugimoto, and
K. Kasahara, “Reduction in the series resistance of the distributed Bragg
reflector in vertical cavities by using quasi-graded superlattices
at the heterointerfaces,” J. Appl. Phys., vol.73,
No.1, pp.21-27 (1993).
[15] H. Kosaka, I. Ogura, M. Sugimoto, H. Saito, T. Numai, and K.
Kasahara, “Pixels consisting of double vertical-cavity detector and single
vertical-cavity laser sections for 2-D bidirectional optical interconnections,”
Jpn. J. Appl. Phys., vol.32, No.1B, pp.600-603
(1993).
[16] K. Kurihara, T. Numai, I. Ogura, H. Kosaka,
M. Sugimoto, and K. Kasahara, “Double-mesa-structure vertical-to-surface
transmission electro-photonic device with a vertical cavity,” Jpn. J. Appl. Phys., vol.32, No.1B, pp.604-608 (1993).
[17] T. Numai, H. Kosaka, I. Ogura, K. Kurihara, M.
Sugimoto, and K. Kasahara, “Indistinct threshold laser operation in a pnpn vertical to surface transmission electro-photonic
device with a vertical cavity,” IEEE J. Quantum Electron., vol.29, No.2,
pp.403-410 (1993).
[18] M. Sugimoto, I.
Ogura, H. Saito, A. Yasuda, K. Kurihara, H. Kosaka, T. Numai, and K. Kasahara, “Surface emitting
devices with distributed Bragg reflectors grown by highly precise molecular
beam epitaxy,” J. Crystal Growth, vol.127, pp.1-4
(1993).
[19] T. Numai, K. Kurihara, I. Ogura, H. Kosaka, M.
Sugimoto, and K. Kasahara, “Effect of sidewall reflector on current versus
light-output in a pnpn vertical to surface
transmission electro-photonic device with a vertical cavity,” IEEE J. Quantum
Electron., vol.29, No.6, pp.2006-2012 (1993).
[20] * T. Numai, “Semiconductor wavelength
tunable optical filters,” (Invited Paper) Int. J. Nonlinear Opt. Phys., vol.2,
No.4, pp.643-659 (1993).
[21] Y. Yamanaka, T.
Numai, K. Kasahara, and K. Kubota, “Optical fiber loop memory using vertical to
surface transmission electro-photonic device,” IEEE/OSA J. Lightwave Technol.,
vol.11, No.12, pp.2140-2144 (1993).
[22] M. Kajita, T. Numai, K. Kurihara, H.
Saito, M. Sugimoto, H. Kosaka, I. Ogura, and K.
Kasahara, “Thermal analysis of laser-emission surface-normal optical devices
with a vertical cavity,” Jpn. J. Appl. Phys., Part 1,
vol.33, No.1B, pp.859-863 (1994).
[23] K. Kurihara, T. Numai, T. Yoshikawa, H. Kosaka,
M. Sugimoto, Y. Sugimoto, and K. Kasahara, “Uniformity improvement of optical
and electrical characteristics in integrated vertical-to-surface transmission
electro-photonic device with a vertical cavity,” Jpn.
J. Appl. Phys., Part 1, vol.33, No.3A, pp.1352-1356 (1994).
[24]* T. Numai,
“Surface-emitting optical devices for 2-D integration,” (Invited Paper) SPIE
Proceedings, vol.2145, pp.58-68 (1994).
[25]* T. Numai
and K. Kasahara, “Low-threshold surface-emitting optical devices,” (Invited
Paper) SPIE Proceedings, vol.2147, pp.122-130 (1994).
[26] T. Numai, K. Kurihara, K. Kühn, H. Kosaka, I. Ogura, M. Kajita, H.
Saito, and K. Kasahara, “Control of light-output polarization for
surface-emitting-laser type device by strained active layer grown on misoriented substrate,” IEEE J. Quantum Electron., vol.31,
No.4, pp.636-642 (1995).
[27] G. Sato, T.
Numai, M. Hoshiyama, I. Suemune,
H. Machida, and N. Shimoyama, “Metalorganic
molecular beam epitaxy growth of ZnSe
with new Zn and Se precursors without precracking,”
J. Crystal Growth, vol.150, pp.734-737 (1995).
[28] G. Sato, T.
Numai, M. Hoshiyama, I. Suemune,
H. Machida, and
[29] M. Arita, A. Avramescu, K. Uesugi, I. Suemune, T. Numai, H.
Machida, and N. Shimoyama, “Self-organized CdSe quantum dots on (100) ZnSe/GaAs surfaces grown by metalorganic
molecular beam epitaxy,” Jpn.
J. Appl. Phys., Part 1, vol.36, pp.4097-4101 (1997).
[30] A. Ueta, I. Suemune, K. Uesugi, M. Arita, A. Avramescu, T. Numai, H. Machida, and N. Shimoyama,
“Selective growth conditions of ZnSe/ZnS heterostructures on (001) GaAs with metalorganic molecular
beam epitaxy,” Jpn. J.
Appl. Phys., Part 1, vol.36, pp.5044-5049 (1997).
[31] T. Numai,
“Analysis of a high density two-dimensional vertical-cavity surface emitting
laser array,” Jpn. J. Appl. Phys., Part 1, vol.36,
pp.6393-6397 (1997).
[32] J. Hirose, K. Uesugi, M. Hoshiyama, T. Numai,
I. Suemune, H. Machida, and N. Shimoyama,
“p-type conductivity control of ZnSe with insertion
of ZnTe:Li submonolayers in metalorganic
molecular-beam epitaxy,” J. Appl. Phys., vol.84,
pp.6100-6104 (1998).
[33] T. Numai,
“Analysis of polarization switching lasers,” Jpn. J.
Appl. Phys., Part 1, vol.38, pp.4746-4755 (1999).
[34] T. Numai, N. Mizutani, and J. Nitta, “Proposal on temperature-insensitive
semiconductor lasers,” Jpn. J. Appl. Phys., Part 1,
vol.38, pp.4764-4767 (1999).
[35] T. Numai,
“Theoretical analysis of switching times in polarization switching lasers,” J.
Appl. Phys., vol.87, pp.1610-1613 (1999).
[36] T. Numai and O.
Kubota, “Analysis of repeated unequally spaced channels for FDM lightwave systems,” IEEE/OSA J. Lightwave Technol., vol.18,
No.5 , pp.656-664
(2000).
[37] Y. Shimosako and T. Numai, “Semiclassical
approach in the analysis of ring laser:
[38] Y. Shimosako and T. Numai, “Semiclassical
approach in the analysis of ring laser: II. mode
coupling due to backscattering and interference,” Jpn.
J. Appl. Phys., vol.39, pp.3901-3996
(2000).
[39] T. Numai,
“Analysis of signal voltage in a semiconductor ring laser gyro,” IEEE J.
Quantum Electron., vol.36, pp.1161-1167 (2000).
[40] T. Numai,
“Analysis of photon recycling in semiconductor ring lasers,” Jpn. J. Appl. Phys., Part 1, vol.39, pp.6535-6538 (2000).
[41] T. Numai, “Beat
frequencies in a ring laser gyro with its refractive index over unity,” J.
Appl. Phys., vol.89, pp.1537-1543 (2001).
[42] N. Mizutani and T. Numai, “Analysis of reflectivity for a beveled
corner mirror in semiconductor ring lasers,” IEEE/OSA J. Lightwave Technol.,
vol.19, No.2 , pp.222-229 (2001).
[43] Y.
Shimosako and T. Numai, “Analysis of light intensity
characteristics in semiconductor ring lasers,” Jpn.
J. Appl. Phys., vol.41, pp.1400-1408 (2002).
[44] T.
Koide, T. Minemoto, H. Takakura, Y. Hamakawa, and T.
Numai, “Control of crystalline orientation of germanium by lateral graphoepitaxy on SiO2 microstructures,” J. Appl.
Phys., vol.97, pp.113530 1-4 (2005).
[45] T.
Mizuta, T. Ikuta, T. Minemoto, H. Takakura, Y. Hamakawa,
and T. Numai, “An optimum design of antireflection coating for spherical
silicon solar cells,” Solar Energy Materials and Solar Cells, vol.
90, pp. 46-56 (2006).
[46] T. Numai, “A
design of absorption layers in stacked color sensors,” Sens. Actuators A,
vol.125, pp. 156-158 (2006).
[47] S. Kojima and T. Numai, “Theoretical analysis of modified repeated
unequally-spaced frequency allocations in FDM lightwave
transmission systems,” IEEE/OSA J. Lightwave
Technol., vol.24, pp.2786-2797 (2006).
[48] T.
Koide, T. Minemoto, H. Takakura, Y. Hamakawa, and T.
Numai, “Imprint lithography with pressing at room temperature,” J. Electrochem Soc., vol.153, pp.G203-G206 (2006).
[49] J. Onishi, S. Kojima, and T. Numai, “Effects of frequency
allocations and zero dispersion frequencies on FDM lightwave
transmission systems,” IEEE/OSA J. Lightwave Technol., vol.25,
pp.1719-1727 (2007).
[50] S. Kojima, T. Hino,
and T. Numai, “Influence of Frequency Allocations and Optical Filters on FDM
Lightwave Transmission Systems,” IEEE/OSA J. Lightwave Technol.,
vol.25, pp.3694-3703 (2007).
[51] J. Onishi,
[52] N.
Kakimoto and T. Numai, “Control of spectral
photosensitivity in stacked color sensors: proposal and theoretical Analysis,” Jpn. J. Appl. Phys., vol.47, pp.4540-4546 (2008).
[53] Y. Nagatani, Y. Ito, J. Onishi, S. Kojima, and T. Numai, “Theoretical analysis of
frequency allocations in FDM lightwave transmission
systems,” J. Lightwave Technol., vol.26, pp.1993-2001 (2008).
[54] J. Onishi, S. Kojima, and T. Numai,
“Effects of frequency/polarization allocations and the zero dispersion
frequency on FDM lightwave transmission systems,”
Opt. Commun., vol.281, pp.3882-3891 (2008).
[55] Y.
Ito, J. Onishi,
[56] N. Shomura, M.
Fujimoto, and T. Numai, “Fiber pump semiconductor
lasers with optical antiguiding layers for horizontal
transverse modes,” J. Quantum Electron., vol.44, pp.819-825
(2008).
[57] N.
Shomura, M. Fujimoto, and T. Numai, “Fiber-pump
semiconductor lasers with optical antiguiding layers
for horizontal transverse modes: dependence on mesa width,” Jpn.
J. Appl. Phys., vol.48, pp.042103-1-8 (2009).
[58] N. Shomura and T. Numai, “Ridge-type semiconductor lasers with optical antiguiding layers for horizontal transverse modes: dependence on step positions,” Jpn. J. Appl. Phys., vol.48, pp.042104-1-9 (2009).
[59] H. Takada and T. Numai, “Ridge-type semiconductor lasers with antiguiding
cladding layers for horizontal transverse modes,”
J. Quantum Electron., vol.45, pp.917-922 (2009).
[60] Y. Ito and T. Numai, “Reduction of four wave mixing noises in FDM optical fiber transmission systems with quaternary bit-phase arranged return-to-zero,” Opt. Commun., vol.282, pp.3989-3994 (2009).
[61] H. Yoshida and T. Numai, “Ridge-type semiconductor lasers with antiguiding layers for horizontal transverse modes: dependence on space in the antiguiding layers,” Jpn. J. Appl. Phys., vol.48, pp.082105-1-5 (2009).
[62] H. Yoshida and T. Numai, “Simulation of ridge-type semiconductor lasers with selectively proton-implanted cladding layers,” Jpn. J. Appl. Phys., vol.49, pp.012101-1-6 (2010).
[63] T. Nishio and T. Numai, “Dependence of total bandwidth and
four-wave-mixing noises in FDM optical fiber transmission systems on the number
of base units,” Opt. Commun., vol.286 pp.313-317 (2013).
[64] T.
Nishio and T. Numai, “Reduction of four-wave-mixing
noises in FDM optical fiber transmission systems in unequally spaced frequency
allocations using base units,” Opt. Commun., vol.294, pp.305-310 (2013).
[65] H. Kato, H. Yoshida, and T. Numai, “Simulation of a Ridge-Type Semiconductor Laser for Separate Confinement of Horizontal Transverse Modes and Carriers,” Opt. Quantum Electron., vol.45, No.7, pp. 573-579 (2013).
[66] G. Chai and T. Numai, “Simulation of a Ridge-Type Semiconductor Laser with Horizontal Coupling of Lateral Modes,” Opt. Quantum Electron., vol.46, No.10, pp. 1217-1223 (2014).
[67] D.
Katsuragawa and T. Numai, “Simulation of a Ridge-Type
Semiconductor Laser with Selective Double-sided
Anti-guiding and Partially Undoped Cladding Layers,” Opt. Quantum
Electron., vol.47, No.6, pp.1381-1387 (2015).
[68] D. Katsuragawa and T. Numai, “Simulation of a Ridge-Type Semiconductor Laser with Partially Formed Anti-guiding Cladding Layers,” Opt. Quantum Electron., vol.47, No.7, pp.2161-2167 (2015).
[69] K. Ichikawa and T. Numai, “Resonance-shifted DFB-LD for asymmetric light output from front/rear facets,” Optik, vol.127, pp. 6253–6257 (2016).
[70] T. Numai, “Enhancement of resonance frequency in a DFB-LD with internally incident modulated light,” Optik, vol.127, pp. 9578–9581 (2016).
[71] K. Ichikawa, S. Ito, and T. Numai, “Enhancement of asymmetry in light output from front/rear facets in resonance-shifted DFB-LDs,” Optik, vol.127, pp. 12078–12084 (2016).
[72] T. Numai, “High resonance frequency in a
coupled cavity DFB-LD with phase-shifted/uniform gratings by photon-photon
resonance,” Optik, vol.202,
163614 (2020).
https://doi.org/10.1016/j.ijleo.2019.163614
[73] T.
Numai, “High resonance frequency in a coupled cavity DFB-LD
with two phase-shifts,” Opt. Quantum Electron., vol.52, No.3 , 150, pp.1-11 (2020). https://doi.org/10.1007/s11082-020-02276-x
[74] T.
Numai, “Over 100 GHz
3-dB down Bandwidth by Direct Modulation of a Coupled Cavity DFB-LD due to
Photon-Photon Resonance,” Opt. Quantum Electron., vol.53, No.92, pp.1-12 (2021). https://doi.org/10.1007/s11082-020-02713-x
[75] T. Hirose and T. Numai, “Simulation of a Ridge-Type Semiconductor Laser with Transversal Diffraction Gratings,” Opt. Quantum Electron., vol.54, No.153, pp.1-9 (2022). https://doi.org/10.1007/s11082-022-03521-1
Letters
[1] T.
Numai, M. Yamaguchi, I. Mito, and K. Kobayashi, “A new grating fabrication
method for phase-shifted DFB LDs,” Jpn. J. Appl.
Phys., Part 2, vol.26, No.11, pp.L1910-L1911 (1987).
[2] H.
Yamada, T. Sasaki, S. Takano, T. Numai, M. Kitamura, and I. Mito, “Low
threshold operation of 1.55 μm GaInAsP/InP DFB LDs entirely grown by MOVPE on InP
grating,” Electron. Lett., vol.24, No.3, pp.147-149 (1988).
[3] T. Numai, M.
Fujiwara, N. Shimosaka, K. Kaede,
M. Nishio, S. Suzuki, and I. Mito, “1.5 μm λ/4-shifted DFB LD filter and 100 Mbit/s
two-channel wavelength signal switching,” Electron. Lett., vol.24, No.4,
pp.236-237 (1988).
[4] T.
Numai, S. Murata, and I. Mito, “Tunable wavelength filters using λ/4-shifted
waveguide grating resonators,” Appl. Phys. Lett.,
vol.53, No.2, pp.83-85 (1988).
[5] M.
Fujiwara, S. Murata, T. Numai, and H. Honmou, “1.55μm
laser diode optical modulator,” Trans. IEICE, vol.E71, No.10, pp.972-974
(1988).
[6] T.
Numai, S. Murata, and I. Mito, “1.5 μm tunable
wavelength filter with wide tuning range and high constant gain using a
phase-controlled distributed feedback laser diode,” Appl. Phys. Lett., vol.53, No.13, pp.1168-1169 (1988).
[7] T.
Numai,
[8] T.
Numai, S. Murata, and I. Mito, “1.5 μm tunable
wavelength filter using a phase-shift-controlled distributed feedback laser
diode with wide tuning range and high constant gain,” Appl. Phys. Lett., vol.54, No.19, pp.1859-1860 (1989).
[9] T.
Numai, “1.5 μm optical filter using a two-section
Fabry-Perot laser diode with wide tuning range and high constant gain,” IEEE
Photonics Technol. Lett., vol.2, No.6, pp.401-403
(1990).
[10] T. Numai, I.
Ogura, H. Kosaka, M. Sugimoto, Y. Tashiro,
and K. Kasahara, “Optical self-routing switch using vertical to surface
transmission electrophotonic devices with
transmission light amplification function,” Electron. Lett., vol.27, No.7,
pp.605-606 (1991).
[11] T. Numai, M.
Sugimoto, I. Ogura, H. Kosaka, and K. Kasahara,
“Surface emitting laser operation in vertical to surface transmission electro-photonic
devices with a vertical cavity,” Appl. Phys. Lett.,
vol.58, No.12, pp.1250-1252 (1991).
[12] T. Numai, M.
Sugimoto, I. Ogura, H. Kosaka, and K. Kasahara,
“Current versus Light-output characteristics with no definite threshold in pnpn vertical to surface transmission electro-photonic
devices with a vertical cavity,” Jpn. J. Appl. Phys.
vol.30, No.4A, pp.L602-L604 (1991).
[13] M. Sugimoto, H. Kosaka, K. Kurihara, I. Ogura, T.
Numai, and K. Kasahara, “Very low threshold current density in vertical-cavity
surface-emitting laser diodes with periodically doped distributed Bragg
reflectors,” Electron. Lett., vol.28, No.4, pp.385-387 (1992).
[14] I. Ogura, H. Kosaka, T. Numai, M. Sugimoto, and K. Kasahara, “Cascadable optical switching characteristics in vertical-to-surface
transmission electrophotonic devices operated as
vertical cavity lasers,” Appl. Phys. Lett., vol.60,
No.7, pp.799-801 (1992).
[15] H. Kosaka, I. Ogura, T. Numai, M. Sugimoto, and K. Kasahara,
“Dependence of laser characteristics on distributed Bragg reflector pairs in
vertical-to-surface transmission electrophotonic
devices,” Electron. Lett., vol.28, No.16, pp.1524-1525 (1992).
[16] T. Numai, K. Kurihara, I. Ogura, H. Kosaka, M.
Sugimoto, and K. Kasahara, “High electronic-optical conversion efficiency in a
vertical-to-surface transmission electro-photonic device with a vertical
cavity,” IEEE Photon. Technol. Lett., vol.5, No.2, pp.136-139
(1993).
[17] K. Kurihara, T. Numai, H. Kosaka, I.
Ogura, M. Sugimoto, and K. Kasahara, “Determination of power reflectivity of
quasi-graded distributed Bragg reflectors using stopband width,” IEEE Photon. Technol. Lett., vol.5, No.3, pp.333-336 (1993).
[18] Y. Yamanaka, T.
Numai, K. Kasahara, and K. Kubota, “Light detection sensitivity of a vertical
cavity structure used in a optical switch device,”
Appl. Phys. Lett., vol.63, No.8, pp.1020-1022 (1993).
[19] T. Numai, T.
Kawakami, T. Yoshikawa, M. Sugimoto, Y. Sugimoto, H. Yokoyama, K. Kasahara, and
K. Asakawa, “Record low threshold current microcavity surface-emitting laser,” Jpn.
J. Appl. Phys., vol.32, No.10B, pp.L1533-L1534 (1993).
[20] H. Kosaka, I. Ogura, H. Saito, M. Sugimoto, K. Kurihara, T. Numai, and K. Kasahara, “Pixels consisting of
a single vertical-cavity laser thyristor and a double
vertical cavity phototransistor,” IEEE Photon. Technol. Lett.,
vol.5, No.12, pp.1409-1411 (1993).
[21] K. Beyzavi, R. A. Linke, G. E. Devlin, I. Ogura, T. Numai, and
K. Kasahara, “Observation of switching energy dependence on illuminating beam
area in the VSTEP optoelectronic switch,” IEEE Photon. Technol. Lett., vol.6, No.2, pp.227-230 (1994).
[22] H. Kosaka, K. Kurihara, A. Uemura, T. Yoshikawa, I. Ogura, T. Numai, M. Sugimoto, and
K. Kasahara, “Uniform characteristics with low threshold and high efficiency
for a single-transverse-mode vertical-cavity surface-emitting laser-type device
array,” IEEE Photon. Technol. Lett., vol.6, No.3,
pp.323-325 (1994).
[23] T.
Koide, T. Minemoto, H. Takakura, Y. Hamakawa, and T.
Numai, “Lateral graphoepitaxy of germanium controlled
by microstructures on SiO2 surface,” Jpn.
J. Appl. Phys., vol.43, pp.L738-L739 (2004).
[24] T.
Numai, T. Koide, T. Minemoto, H. Takakura, and Y. Hamakawa,
“Nanoimprint lithography using Novolak-type
photoresist and soft mold at room temperature,” Jpn. J. Appl. Phys., vol.43, pp.L794-L796 (2004).