12037-79-5Relevant articles and documents
Triplet-to-singlet conversion in the exciton system in β-ZnP2 - Anti-Stokes exciton luminescence
Nakamura, Kaizo,Shigoku, Minoru,Kondo, Kanji,Arimoto, Osamu
, p. 1890 - 1893 (1998)
A new type of experiment was performed to investigate the effective nonradiative process causing the fast decay of the forbidden 1s triplet exciton luminescence with polarization E//b in β-ZnP2. Excitation spectra of anti-Stokes 1s singlet exciton luminescence with E//c have been measured by varying the excitation energy with E//b around the 1s triplet exciton absorption peak which is located about 2 meV below the singlet exciton luminescence. A sharp peak of excitation efficiency has been confirmed at the triplet exciton resonance for the first time. Temperature dependence of the excitation peak is in accordance with the thermal behavior of the singlet exciton polariton luminescence both from lower- and upper-branches. This anti-Stokes acoustic phonon scattering of triplet exciton into singlet states is one of the main causes of the short lifetime of triplet exciton in β-ZnP2. Spin flip mechanism is briefly discussed.
Resonant Brillouin scattering of exciton-polaritons in β-ZnP2
Sugisaki, Mitsuru,Arimoto, Osamu,Nakamura, Kaizo
, p. 3134 - 3142 (2001)
The secondary omission spectra of β-ZnP2 under the resonant excitation in the 1s exciton region were investigated in detail. Several scattering lines with the Stokes shifts of less than 6 meV were found. By analyzing the experimental results using a model based on the exciton-polariton picture, we attributed the observed scattering lines to the Brillouin lines. The sound velocities of the LA and TA phonons were derived to be υLA = 4.8(±0.2) × 105 cm/s and υTA = 2.8(±0.2) × 105 cm/s, respectively. The resonant enhancement of the Brillouin lines was observed around the transverse exciton energy ET, which reflects high transmissivity and a small group velocity of the exciton-polaritons at ET. We also found that the Rayleigh scattering line was resonantly enhanced between the longitudinal exciton energy EL and ET due to the surface roughness, which explains the drastic reduction of the luminescence from the lower branch polaritons in intensity reported earlier. The excitation energy dependence of the Brillouin line width is also discussed.
Two-temperature synthesis of ZnGeP2
Verozubova,Gribenyukov,Mironov
, p. 1040 - 1045 (2007)
We describe a modified two-temperature process for reproducible high-volume (up to 500 g) synthesis of the nonlinear-optical semiconductor ZnGeP 2, which enables the preparation of nominally stoichiometric material. The major reaction intermediates in the two-temperature ZnGeP 2 synthesis are ZnP2, Zn3P2, GeP, and Ge. Using x-ray diffraction, we refined the interplanar spacings in the tetragonal structure of ZnGeP2 and fcc structure of GeP and indexed peaks missing in the PDF cards 33-1471 (ZnGeP2) and 21-353 (GeP).
Two-Phonon Assisted Indirect Exciton Luminescence in α-ZnP2
Nakamura, Kaizo,Arimoto, Osamu,Eguchi, Masaru,Nishikawa, Mitsuo
, p. 493 - 498 (1997)
Luminescence spectra of tetragonal ZnP2 crystal are measured at various temperatures. Below the indirect exciton threshold, about 30 intrinsic indirect exciton luminescence bands are confirmed. Amidst the broad bound exciton luminescence band,
Magneto-optical effects of the Wannier exciton in a biaxial ZnP2 crystal. I
Taguchi, Satoshi,Goto, Takenari,Takeda, Masayasu,Kido, Giyuu
, p. 3256 - 3261 (1988)
An exciton absorption spectrum of a monoclinic ZnP2 crystal for E // b polarization has been measured in magnetic fields up to 14 T. From behaviors of the exciton line series in the magnetic fields parallel to the a-, b- and c-axes, it is found that the exciton is of s-type and has a paramagnetic splitting with the g-factor of 4. Analyzing the diamagnetic shift in a biaxial crystal, we estimate exciton reduced masses and background dielectric constants in the a-, b- and c-axes to be μa,=(0.39±0.03)m 0, μb= (0.45±0.03)m0, μc=(0.15±0.01)m0=7.8±0.2, εb=10.0±0.2 and εc= 9.7±0.2, respectively.
Two-photon absorption into excited states of excitonic molecules and their inelastic scattering in ZnP2
Dmitruk, I.,Goto, T.,Kasuya, A.,Yanchuk, Z.
, p. 1 - 6 (2008/10/08)
Excited states of excitonic molecules have been observed by the direct method of giant two-photon absorption in a monoclinic ZnP2 single crystal. Their origin and comparison with theoretical expectations are discussed. Photoluminescence of thermalized and nonthermalized cold excitonic molecules was studied under resonant two-photon excitation into their ground and excited states. An alternative mechanism of inelastic scattering of excitonic molecules is suggested.
Vapor Growth of Tetragonal ZnP2 Crystals
Yakimovich,Trukhan
, p. 1085 - 1087 (2008/10/08)
Vapor growth of α-ZnP2 single crystals from polycrystalline source material is studied. Crystals of the tetragonal phase are grown in the temperature range 1045-1120 K. Their length-to-thickness ratio depends on the radial temperature gradient in the vicinity of the growing crystal.
