"Floquet Weyl states at one-photon resonance: An origin of nonperturbative optical responses in three-dimensional materials"
Yoshua Hirai, Shun Okumura, Naotaka Yoshikawa, Takashi Oka, and Ryo Shimano, Phys. Rev. Research 6, L012027 (2024).
2023
"Ultrafast stroboscopic time-resolved magneto-optical imaging of domain wall motion in Pt/GdFeCo wires induced by a current pulse"
Kazuma Ogawa, Naotaka Yoshikawa, Mio Ishibashi, Kay Yakushiji, Arata Tsukamoto, Masamitsu Hayashi, and Ryo Shimano, Phys. Rev. Research 5, 033151 (2023).
"Near-infrared light-induced superconducting-like state in underdoped YBa2Cu3Oy studied by c-axis terahertz third-harmonic generation"
Kota Katsumi, Morihiko Nishida, Stefan Kaiser, Shigeki Miyasaka, Setsuko Tajima, and Ryo Shimano, Phys. Rev. B 107, 214506 (2023).
"Light-induced coherent interlayer transport in stripe-ordered
La1.6−xNd0.4SrxCuO4"
Morihiko Nishida, Kota Katsumi, Dongjoon Song, Hiroshi Eisaki, Ryo Shimano, Phys. Rev. B 107, 174523 (2023).
"Ultrafast Dynamics of Intrinsic Anomalous Hall Effect in the Topological Antiferromagnet Mn3Sn"
Takuya Matsuda, Tomoya Higo, Takashi Koretsune, Natsuki Kanda, Yoshua Hirai, Hanyi Peng, Takumi Matsuo, Naotaka Yoshikawa, Ryo Shimano, Satoru Nakatsuji, and Ryusuke Matsunaga, Phys. Rev. Lett. 130, 126302 (2023).
"Anomalous Hall effect of light-driven three-dimensional Dirac electrons in bismuth"
Yoshua Hirai, Naotaka Yoshikawa, Masashi Kawaguchi, Masamitsu Hayashi, Shun Okumura, Takashi Oka, Ryo Shimano, arXiv:2301.06072.
"Light-induced chiral gauge field in a massive 3D Dirac electron system"
Naotaka Yoshikawa, Yoshua Hirai, Kazuma Ogawa, Shun Okumura, Kohei Fujiwara, Junya Ikeda, Takashi Koretsune, Ryotaro Arita, Aditi Mitra, Atsushi Tsukazaki, Takashi Oka, Ryo Shimano, arXiv:2209.11932.
"Optical response of the Leggett mode in multiband superconductors in the linear response regime"
Takumi Kamatani, Sota Kitamura, Naoto Tsuji, Ryo Shimano, Takahiro Morimoto, Phys. Rev. B 105, 094520 (2022).
"Terahertz pulse-driven collective mode in the nematic superconducting state of Ba1−xKxFe2As2"
Romain Grasset, Kota Katsumi, Pierre Massat, Hai-Hu Wen, Xian-Huin Chen, Yann Gallais, and Ryo Shimano, npj Quantum Materials 7, Article number: 4 (2022).
2021
"Light-induced enhancement of superconductivity in iron-based superconductor FeSe0.5Te0.5"
Kazuki Isoyama, Naotaka Yoshikawa, Kota Katsumi, Jeremy Wong, Naoki Shikama, Yuki Sakishita, Fuyuki Nabeshima, Atsutaka Maeda & Ryo Shimano, Commun. Phys. 4, 160 (2021).
"Ultrafast switching to an insulating-like metastable state by amplitudon excitation of a charge density wave"
Naotaka Yoshikawa, Hiroki Suganuma, Hideki Matsuoka, Yuki Tanaka, Pierre Hemme, Maximilien Cazayous, Yann Gallais, Masaki Nakano, Yoshihiro Iwasa & Ryo Shimano, Nature Physics 17, 909 (2021).
"Switchable generation of azimuthally- and radially-polarized terahertz beams from a spintronic terahertz emitter"
Hiroaki Niwa, Naotaka Yoshikawa, Masashi Kawaguchi, Masamitsu Hayashi, and Ryo Shimano, Optics Express 29, 13331 (2021). Editors' Pick
2020
"Terahertz Emission from Bismuth Thin Films Induced by Excitation with Circularly Polarized Light"
Yoshua Hirai, Naotaka Yoshikawa, Hana Hirose, Masashi Kawaguchi, Masamitsu Hayashi, and Ryo Shimano, Phys. Rev. Appl. 14, 064015 (2020). Editors' Suggestion
"Nonreciprocal Terahertz Second-Harmonic Generation in Superconducting NbN under Supercurrent Injection"
Sachiko Nakamura, Kota Katsumi, Hirotaka Terai, and Ryo Shimano, Phys. Rev. Lett. 125, 097004 (2020).
"Superconducting fluctuations probed by the Higgs mode in Bi2Sr2CaCu2O8+x thin films"
Kota Katsumi, Zhi Zhong Li, Hélène Raffy, Yann Gallais, Ryo Shimano, Phys. Rev. B 102, 054510 (2020).
"Phase-resolved Higgs response in superconducting cuprates"
Hao Chu, Min-Jae Kim, Kota Katsumi, Sergey Kovalev, Robert David Dawson, Lukas Schwarz, Naotaka Yoshikawa, Gideok Kim, Daniel Putzky, Zhi Zhong Li, Hélène Raffy, Semyon Germanskiy, Jan-Christoph Deinert, Nilesh Awari, Igor Ilyakov, Bertram Green, Min Chen, Mohammed Bawatna, Georg Cristiani, Gennady Logvenov, Yann Gallais, Alexander V. Boris, Bernhard Keimer, Andreas P. Schnyder, Dirk Manske, Michael Gensch, Zhe Wang, Ryo Shimano, and Stefan Kaiser Nature Communications 11, 1793 (2020).
"Light-driven electron-hole Bardeen-Cooper-Schrieffer-like state in bulk GaAs"
Yuta Murotani, Changsu Kim, Hidefumi Akiyama, Loren N. Pfeiffer, Ken W. West, and Ryo Shimano Phys. Rev. Lett. 123, 197401 (2019). Editors' Suggestion
"Light-induced nonequilibrium response of the superconducting cuprate La2−xSrxCuO4"
Hiroaki Niwa, Naotaka Yoshikawa, Kaito Tomari, Ryusuke Matsunaga, Dongjoon Song, Hiroshi Eisaki, and Ryo Shimano, Phys. Rev. B 100, 104507 (2019). Editors' Suggestion
"Charge carrier dynamics of FeSe thin film investigated by terahertz magneto-optical spectroscopy"
Naotaka Yoshikawa, Masayuki Takayama, Naoki Shikama, Tomoya Ishikawa, Fuyuki Nabeshima, Atsutaka Maeda, Ryo Shimano, Phys. Rev. B 100, 035110 (2019).
"Infrared Activation of the Higgs Mode by Supercurrent Injection in Superconducting NbN"
Sachiko Nakamura, Yudai Iida, Yuta Murotani, Ryusuke Matsunaga, Hirotaka Terai, and Ryo Shimano, Phys. Rev. Lett. 122, 257001 (2019).
"Nonlinear optical response of collective modes in multiband superconductors assisted by nonmagnetic impurities"
Yuta Murotani and Ryo Shimano, Phys. Rev. B 99, 224510 (2019).
2018
"Higgs mode in the d-wave superconductor Bi2Sr2CaCu2O8+x driven by an intense terahertz pulse"
Kota Katsumi, Naoto Tsuji, Yuki I. Hamada, Ryusuke Matsunaga, John Schneeloch, Ruidan D. Zhong, Genda. D. Gu, Hideo Aoki, Yann Gallais, and Ryo Shimano, Phys. Rev. Lett. 120, 117001 (2018). Editors' Suggestion
"Ultrafast terahertz nonlinear optics of Landau level transitions in a monolayer graphene"
Go Yumoto, Ryusuke Matsunaga, Hiroki Hibino, and Ryo Shimano, Phys. Rev. Lett. 120, 107401 (2018).
"Terahertz field-induced ionization and perturbed free induction decay of excitons in bulk GaAs"
Yuta Murotani, Masayuki Takayama, Fumiya Sekiguchi, Changsu Kim, Hidefumi Akiyama, and Ryo Shimano, J. Phys. D: Appl. Phys. 51, 114001 (2018).
2017
"Rate Equation Analysis of the Dynamics of First-order Exciton Mott Transition"
F. Sekiguchi and R. Shimano, J. Phys. Soc. Jpn. 86, 103702 (2017).
"Polarization-resolved terahertz third-harmonic generation in a single-crystal superconductor NbN: Dominance of the Higgs mode beyond the BCS approximation"
R. Matsunaga, N. Tsuji, K. Makise, H. Terai, H. Aoki, and R. Shimano, Phys. Rev. B 96, 020505(R) (2017).
"Anomalous metal phase emergent on the verge of an exciton Mott transition"
F. Sekiguchi, T. Mochizuki, C. Kim, H. Akiyama, L. N. Pfeiffer, K. W. West, and R. Shimano, Phys. Rev. Lett. 118, 067401 (2017).
"Nonlinear terahertz spectroscopy of Higgs mode in s-wave superconductors"
R. Matsunaga and R. Shimano, Phys. Scr. 92, 024003 (2017).
"Light-induced collective pseudospin precession resonating with Higgs mode in a superconductor"
R. Matsunaga, N. Tsuji, H. Fujita, A. Sugioka, K. Makise, Y. Uzawa, H. Terai, Z. Wang, H. Aoki, and R. Shimano, Science 345, 1145 (2014).
"Higgs Amplitude Mode in the BCS Superconductors Nb1-xTixN induced by Terahertz Pulse Excitation"
R. Matsunaga, Y. I. Hamada, K. Makise, Y. Uzawa, H. Terai, Z. Wang, and R. Shimano, Phys. Rev. Lett. 111, 057002 (2013).
"Quantum Faraday and Kerr rotations in graphene"
R. Shimano, G. Yumoto, J. Y. Yoo, R. Matsunaga, S. Tanabe, H. Hibino, T. Morimoto, and H. Aoki, Nature Commun. 4, 1841 (2013).
2012
"Nonequilibrium BCS state dynamics induced by intense terahertz pulses in a superconducting NbN film"
R. Matsunaga and R. Shimano, Phys. Rev. Lett. 109, 187002 (2012).
"Chirality of matter shows up via spin excitations"
S. Bordacs, I. Kezsmarki, D. Szaller, L. Demko, N. Kida, H. Murakawa, Y. Onose, R. Shimano, T. Room, U. Nagel, S. Miyahara, N. Furukawa, and Y. Tokura, Nature Physics 8, 734 (2012).
"Magnetoelectric resonance with electromagnons in a perovskite helimagnet"
Y. Takahashi, R. Shimano, Y. Kaneko, H. Murakawa, and Y. Tokura, Nature Physics 8, 121 (2012).
2011
"Magnetically driven ferroelectric atomic displacements in orthorhombic YMnO3"
D. Okuyama, S. Ishiwata, Y. Takahashi, K. Yamauchi, S. Picozzi, K. Sugimoto, H. Sakai, M. Takata, R. Shimano, Y. Taguchi, T. Arima, and Y. Tokura, Phys. Rev. B 84, 054440 (2011).
"Terahertz Faraday rotation induced by an anomalous Hall effect in the itinerant ferromagnet SrRuO3"
R. Shimano, Y. Ikebe, K. S. Takahashi, M. Kawasaki, N. Nagaosa, and Y.Tokura, EPL 95, 17002 (2011).
"Cooling dynamics of photoexcited carriers in Si studied using optical pump and terahertz probe spectroscopy"
T. Suzuki and R. Shimano, Phys. Rev. B 83, 085207 (2011).
"Optical investigation of the collective dynamics of charge-orbital density waves in layered manganites"
J. Fujioka, Y. Ida, Y. Takahashi, N. Kida, R. Shimano, and Y. Tokura, Phys. Rev. B 82, 140409(R) (2010). Editors' Suggestion
"Electromagnons in the spin collinear state of a triangular lattice antiferromagnet"
S. Seki, N. Kida, S. Kumakura, R. Shimano, and Y. Tokura, Phys. Rev. Lett. 105, 097207 (2010).
"Room temperature terahertz electro-optic modulation by excitons in carbon nanotubes"
T. Ogawa, S. Watanabe, N. Minami, and R. Shimano, Appl. Phys. Lett. 97, 041111 (2010).
(selected for the August 2010 issue of Virtual Journal of Nanoscale Science & Technology, Volume 22, Issue 6 (2010),
and Virtual Journal of Ultrafast Science, Volume 9, Issue 8 (2010).)
"Optical Hall effect in the integer quantum Hall regime"
Y. Ikebe, T. Morimoto, R. Masutomi, T. Okamoto, H. Aoki, and R. Shimano, Phys. Rev. Lett. 104, 256802 (2010).
"Ultrafast photo-induced insulator-to-metal transition in the spin density wave system of (TMTSF)2PF6"
S. Watanabe, R. Kondo, S. Kagoshima, and R. Shimano, Physica B 405, S360-S362 (2010).
"Electromagnons in the multiferroic state of perovskite manganites with symmetric exchange striction"
Y. Takahashi, S. Ishiwata, S. Miyahara, Y. Kaneko, N. Furukawa, Y. Taguchi, R. Shimano, and Y. Tokura, Phys. Rev. B 81, 100413(R) (2010).
"Above-room-temperature ferroelectricity in a single-component molecular crystal"
S. Horiuchi, Y. Tokunaga, G. Giovannetti, S. Picozzi, H. Itoh, R. Shimano, R. Kumai, and Y. Tokura, Nature 463, 789-792 (2010).
"Charge-ordering-induced polar domains and domain walls in a bilayered manganite Pr(Sr0.15Ca0.85)2Mn2O7"
H. Itoh, Y. Tokunaga, N. Kida, R. Shimano, and Y. Tokura, Appl. Phys. Lett. 96, 032902 (2010).
2009
"Observation of ultrafast photoinduced closing and recovery of the spin-density-wave gap in (TMTSF)2PF6"
S. Watanabe, R. Kondo, S. Kagoshima, and R. Shimano, Phys. Rev. B 80, 220408(R) (2009). Editors' Suggestion
(selected for the January 2010 issue of Virtual Journal of Ultrafast Science,Volume 9, Issue1 (2010).)
"Electric-dipole-active magnetic resonance in the conical-spin magnet Ba2Mg2Fe12O12"
N. Kida, D. Okuyama, S. Ishiwata, Y. Taguchi, R. Shimano, K. Iwasa, T. Arima, and Y. Tokura, Phys. Rev. B 80, 220406(R) (2009).
"Lattice dynamics in the ab- and bc-spiral spin-ordered states of perovskite manganites"
J. S. Lee, N. Kida, Y. Yamasaki, R. Shimano, and Y. Tokura, Phys. Rev. B 80, 134409 (2009).
"Anisotropic polarization $\pi$-molecular skeleton coupled dynamics in proton-displacive organic ferroelectrics"
J. Fujioka, S. Horiuchi, N. Kida, R. Shimano, and Y. Tokura, Phys. Rev. B 80, 125134 (2009).
"Time-resolved formation of excitons and electron-hole droplets in Si studied using terahertz spectroscopy"
T. Suzuki and R. Shimano, Phys. Rev. Lett. 103, 057401 (2009).
"Far-infrared optical study of electromagnons and their coupling to optical phonons in Eu1−xYxMnO3 (x=0.1, 0.2, 0.3, 0.4, and 0.45)"
Y. Takahashi, Y. Yamasaki, N. Kida, Y. Kaneko, T. Arima, R. Shimano, and Y. Tokura, Phys. Rev. B 79, 214431 (2009). Editors' Suggestion
"Vortex dynamics in a NbN film studied by terahertz spectroscopy"
Y. Ikebe, R. Shimano, M. Ikeda, T. Fukumura, and M. Kawasaki, Phys. Rev. B 79, 174525 (2009).
(Selected for Virtual Journal of Applications of Superconductivity, Volume 16, No.11, (2009).)
"Systematics of electromagnons in the spiral spin-ordered states of RMnO3"
J. S. Lee, N. Kida, S. Miyahara, Y. Takahashi, Y. Yamasaki, R. Shimano, N. Furukawa, and Y. Tokura, Phys. Rev. B 79, 180403(R) (2009).
2008
"Spin-density-wave gap in (TMTSF)2PF6 probed by reflection-type terahertz time domain spectroscopy"
S. Watanabe, R. Kondo, S. Kagoshima, and R. Shimano, Phys. Stat. Solidi (b) 245, 2688 (2008).
"Characterization of doped silicon in low carrier density region by terahertz frequency Faraday effect"
Y. Ikebe and R. Shimano, Appl. Phys. Lett. 92, 012111 (2008).
"Evidence for an electric dipole active continuum band of spin excitations in multiferroic TbMnO3"
Y. Takahashi, N. Kida, Y. Yamasaki, J. Fujioka, T. Arima, R. Shimano, S. Miyahara, M. Mochizuki, N. Furukawa, and Y. Tokura, Phys. Rev. Lett. 101, 187201 (2008).
"Electrically driven spin excitation in a ferroelectric magnet DyMnO3"
N. Kida, Y. Ikebe, Y. Takahashi, J. P. He, Y. Kaneko, Y.Yamasaki, R. Shimano, T. Arima, N. Nagaosa and Y. Tokura, Phys. Rev. B 78, 104414 (2008). Editors' Suggestion
2007
"Dielectric properties of single-walled carbon nanotubes in the terahertz frequency range"
H. Nishimura, N. Minami and R. Shimano, Appl. Phys. Lett. 91, 011108 (2007).
"Compact terahertz time domain spectroscopy system with diffraction-limited spatial resolution"
S. Watanabe and R. Shimano, Rev. Sci. Instr. 78, 103906 (2007).
2005
"Frequency tunable circular polarization control of terahertz radiation"
R. Shimano, H. Nishimura and T. Sato, Jpn. J. Appl. Phys. 44, L676 (2005).
"Study of orthoexciton-to-paraexciton conversion in Cu2O by excitonic Lyman spectroscopy"
M. Kubouchi, K. Yoshioka, R. Shimano, A. Mysyrowicz, and M. Kuwata-Gonokami, Phys. Rev. Lett. 94, 016403 (2005).
"Optical activity in chiral gold nanorings"
K. Jefimovs, N. Saito, Y. Ino, T. Vallius, P. Vahimaa, J. Turunen, R. Shimano, M. Kauranen, Y. Svirko, M. Kuwata-Gonokami, Microelectronic Engineering 78-79, 448-451 (2005).
2004 and earlier
"Terahertz time domain magneto-optical ellipsometry in reflection geometry"
Y. Ino, R. Shimano, Y. Svirko, and M. Kuwata-Gonokami, Phys. Rev. B 70, 155101 (2004).
"Numerical phase correction method for terahertz time-domain reflection spectroscopy"
E. M. Vartiainen, Y. Ino, R. Shimano, M. Kuwata-Gonokami, Y. Svirko, and K. Peiponenn, J. Appl. Phys. 96, 4171 (2004).
"Observation of the spin-charge thermal isolation of ferromagnetic Ga0.94Mn0.06As by time-resolved magneto-optical measurement"
E. Kojima, R.Shimano, Y. Hashimoto, S. Katsumoto, Y. Iye, and M. Kuwata-Gonokami, Phys. Rev. B 68, 193203 (2003).
"Creation of supercooled exciton gas and transformation to electron-hole droplets in diamond"
M. Nagai, R. Shimano, K. Horiuchi, M. Kuwata-Gonokami, Phys. Rev. B 68, 081202(R) (2003).
"Phase diagram of the quantum degenerate electron-hole system in diamond"
M. Nagai, R. Shimano, K. Horiuchi, M. Kuwata-Gonokami, Phys. Stat. Solidi (b) 238, 509-512 (2003).
"Efficient two-photon light amplification by a coherent biexciton wave"
R. Shimano, Yu. P Svirko, A. Mysyrowicz, and M. Kuwata-Gonokami, Phys. Rev. Lett. 89, 233601 (2002).
"Terahertz frequency Hall measurement by magneto-optical Kerr spectroscopy in InAs"
R. Shimano, Y. Ino, Yu. P. Svirko, M. Kuwata-Gonokami, Appl. Phys. Lett. 81, 199 (2002).
"Formation of a high T-c electron-hole liquid in diamond"
R. Shimano, M. Nagai, K. Horiuch, M. Kuwata-Gonokami, Phys. Rev. Lett. 88, 057404 (2002).
"Electron-hole droplet formation in direct-gap semiconductors observed by mid-infrared pump-probe spectroscopy"
M. Nagai, R. Shimano, M. Kuwata-Gonokami, Phys. Rev. Lett. 86, 5795 (2001).
"Gigantic reflectance anisotropy of the [110] face of cubic ZnSe in the excitonic part of the spectrum"
G. Mohs, S. Dhanjal, T. Kise, M. Shirane, R. Shimano, Y. P. Svirko, K. Ohkawa, N.I. Zheludev, M. Kuwata-Gonokami, J. Phys. Soc. Jpn. 69, 3458 (2000).
"Quantitative study of exciton-exciton interaction in a GaAs microcavity"
C, Ramkumar, T. Aoki, R. Shimano, Y. P. Svirko, T. Kise, T. Someya, H. Sakaki, and M. Kuwata-Gonokami, J. Phys. Soc. Jpn. 69, 2439 (2000).
"Role of exciton-exciton interaction on resonant third-order nonlinear optical responses"
M. Kuwata-Gonokami, T. Aoki, C. Ramkumar, R. Shimano, Yu. P. Svirko, J. Luminescence. 87-89, 162-167 (2000).
"Coherent dynamics of excitons in an island-inserted GaAs/AlAs quantum well structure: suprression of phase relaxation and a deep quantum beat"
T. Matsusue, H. Akiyama, T. Saiki, C. Ramkumar, M. Shirane, R. Shimano, M. Kuwata-Gonokami, and H. Sakaki, Jpn. J. Appl. Phys. 38, 2735 (1999).
"Degenerate four wave mixing measurements on an exciton-photon coupled system in a semiconductor microcavity"
M. Shirane, C. Ramkumar, Y. P Svirko, H. Suzuura, S. Inouye, R. Shimano, T. Someya, H. Sakaki, M. Kuwata-Gonokami, Phys. Rev. B 58, 7978 (1998).
"Optical detection of crystallographic domains zinc-blende crystal"
G. Mohs, R. Shimano, T. Kise, M. Shirane, M. Kuwata-Gonokami, K. Ohkawa, S. Dhanjal, Y. Svirko, N. Zheludev, Appl. Phys. Lett. 73, 1511 (1998).
"On the gain mechanism in GaN based laser diodes"
G. Mohs, T. Aoki, R. Shimano, M. Kuwata-Gonokami, and S. Nakamura, Solid State Commun. 108, 105-109 (1998).
"Failure of the modal gain model in a GaN based laser diode"
G. Mohs, T. Aoki, M. Nagai, R. Shimano, M. Kuwata-Gonokami, and S. Nakamura, Solid State Commun. 104, 643-648 (1997).
"Spherical cavity-mode laser with self-organized CuCl microspheres"
M. Nagai, F. Hoshino, S. Yamamoto, R. Shimano, and M. Kuwata-Gonokami, Optics Lett. 22, 1630-1632 (1997).
"Parametric scattering of cavity polaritons"
M. Kuwata-Gonokami, S. Inouye, H. Suzuura, M. Shirane, R. Shimano, T. Someya, and H. Sakaki, Phys. Rev. Lett. 79, 1341 (1997).
"Exciton-to biexciton transition in quasi-one-dimensional organics"
S. Mazumdar, M. Kuwata-Gonokami, N. Peyghambarian, K. Meissner, B. Fluegel, Y. Sato, K. Ema, R. Shimano, F. Guo, T. Tokihiro, H. Ezaki, E. Hanamura, J. Chem. Phys. 104, 9292 (1996).
"Efficient phase conjugation wave generation from a GaAs single quantum well in microcavity"
R. Shimano, S. Inouye, M. Kuwata-Gonokami, T. Nakamura, M. Yamanishi and I. Ogura, Jpn. J. Appl. Phys. 34, L817-L820 (1995).
"Observation of Autler-Townes splitting of biexcitons in CuCl"
Ryo Shimano and Makoto Kuwata-Gonokami, Phys. Rev. Lett. 72, 530 (1994).
"Exciton strings in an organic charge-transfer crystal"
M. Kuwata-Gonokami, N. Peyghambarian, K. Meissner, B. Fluegel, Y. Sato, K. Ema, R. Shimano, S. Mazumdar, F. Guo, T. Tokihiro, H. Ezaki, E. Hanamura, Nature 367, 47-48 (1994).
"Excitonic n-strings in linear chains"
H. Ezaki, M. Kuwata-Gonokami, R. Shimano, K. Ema, E. Hanamura, B. Fluegel, K. Meissner, S. Mazumdar, N. Peyghambarian, Solid State Commun. 88, 211-216 (1993).
"Optical nonlinearities and dynamics of an exciton-biexciton system in CuCl in the weak excitation regime"
M. Kuwata-Gonokami, R. Shimano, J. Iwamatsu, H. Akiyama, T. Kuga, and M. Matsuoka, Phys. Stat. Sol. 159, 347-351 (1990).