The temperature dependence of the Raman-active mode frequencies in indium sulfide was measured in the range from 10 to 300 K. The analysis of the temperature dependence of the Ag intralayer optical modes show that Raman frequency shift results from the change of harmonic frequency with volume expansion and anharmonic coupling to phonons of other branches. The pure-temperature contribution (phon...

A detailed model is proposed to explain the electroluminescence spectrum from metal–oxide– silicon tunneling diodes. This model includes phonon-assisted processes and exciton involvement. According to this model, the main peak and the low-energy tail of the electroluminescence spectrum are attributed to the transverse optical phonon and the two-phonon assisted recombination, respectively. With ...

We comprehensively examine the importance of phonons on the optical properties of GaN. Using Raman and photoluminescence PL spectroscopies, the energies and linewidths of optic phonons, excitons, and discrete phonon sidebands PSBs are studied between 20 and 325 K. The temperature dependence of the A1 LO phonon energy and linewidth are described by a combined twoand three-phonon decay process. T...

The main goal of the present work is to study the coherent phonon in strongly confined CdSe quantum dots (QDs) under varied pump fluences. The main characteristics of coherent phonons (amplitude, frequency, phase, spectrogram) of CdSe QDs under the red-edge pump of the excitonic band [1S(e)-1S3/2(h)] are reported. We demonstrate for the first time that the amplitude of the coherent optical long...

We show that recently reported [5] unusual hardening of optical phonons renormalized by the electron-phonon interaction [5] is due to the neglect of screening effects. When the electron-ion interaction is properly screened optical phonons soften in three dimension. It is important that for shortwavelength optical phonons screening is static while for long-wavelength optical phonons screening is...

Based on the dielectric continuum model and transfer-matrix method, the completing polar optical phonon states in a wurtzite GaN-based superlattice (SLs) with arbitrary-layer complex bases are investigated. It is proved that 2 types of phonon modes probably exist in a wurtzite nitride SL with n-layer complex bases. The analytical phonon states of these modes and their dispersive equations in th...

We theoretically propose optical phonon lasing in a double quantum dot (DQD) fabricated on a semiconductor substrate. No additional cavity or resonator is required. An electron in the DQD is found to be coupled to only two longitudinal optical phonon modes that act as a natural cavity. When the energy level spacing in the DQD is tuned to the phonon energy, the electron transfer is accompanied b...

Thermal transport and phonon-phonon coupling in monolayer hexagonal boron nitride (h-BN) under equibiaxial strains are investigated from first principles. Phonon spectra at elevated temperatures have been calculated from perturbation theory using the third-order anharmonic force constants. The stiffening of the out-of-plane transverse acoustic mode (ZA) near the Brillouin zone center and the in...

The optical properties of quantum dots embedded in a catalytically grown semiconductor nanowire are studied theoretically. In comparison to dots in a bulk environment, the excitonic absorption is strongly modified by the one-dimensional character of the nanowire phonon spectrum. In addition to pronounced satellite peaks due to phonon-assisted absorption, we find a finite width of the zero-phono...