phonons in nanostructures

... simple continuum models of phonon confinement. Since dimensional confinement of phonons restricts the phase space of the phonons, it is certain that carrier-phonon interactions in nanostructures ... Frohlich, and piezoelectric interactions in a variety of nanostructures including quantum wells, quantum wires, and quantum dots. These interactions playa dominant role in determining...

Ngày tải lên: 04/06/2014, 14:40

... operator X. Using Hamiltonian in Eq.(1) and realizing operator algebraic calculations, we obtain a set of coupled quantum kinetic equations for phonons. The equation for the acoustic phonons can ... equations for the phonons. The analytic expression of parametric transformation coefficient of acoustic and optical phonons in doped superlattices is obtained, that depends non-linea...

Ngày tải lên: 22/03/2014, 11:20

... peaks in the thinner films are slightly wider, indicating longer interatomic distances or larger tensile stress and stronger anharmonicity in thinner films. The band gap in 064307-4 ORIGIN OF COHERENT ... Bi 2 Te 3 thin film illuminated by 30 ◦ incident pump beam. is determined to be 2636 K. It is then found from Eq. (2) that in our case, the thermal force f thermal = 1.42 × 10 16 N/m 3...

Ngày tải lên: 06/05/2014, 08:54

... 2007; published online 21 June 2007͒ Energy coupling to coherent phonons in Bi during femtosecond laser–bismuth interaction is investigated using a double-pulse femtosecond pulse train generated from ... Coupling of ultrafast laser energy to coherent phonons in bismuth Alexander Q. Wu and Xianfan Xu a͒ School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907...

Ngày tải lên: 06/05/2014, 08:55

... peaks in the thinner films are slightly wider, indicating longer interatomic distances or larger tensile stress and stronger anharmonicity in thinner films. The band gap in 064307-4 ORIGIN OF COHERENT ... Bi 2 Te 3 thin film illuminated by 30 ◦ incident pump beam. is determined to be 2636 K. It is then found from Eq. (2) that in our case, the thermal force f thermal = 1.42 × 10 16 N/m 3...

Ngày tải lên: 06/05/2014, 08:58

... tunneling. Some tunneling theories accounting the interaction of electrons with phonons are known [5,6], in which the tunneling is temperature-dependent process. In the presented paper, we will interpret ... to the phonon- assisted tunneling. The electron population in the traps is assumed to be independent of bias voltage due to the continuous filling the traps in the interface laye...

Ngày tải lên: 16/03/2014, 15:18

... Semiconductors potential in uncovering new phenomena in nanoscience, but also for their interesting quantum device applications [42–45]. In ultrathin films, the restriction of the motion of the carriers in the ... been investigated [158–165]. These studies revealed some of the interesting features that had been seen in bulk PbTe, such as Fermi level pinning in the case of supercond...

Ngày tải lên: 29/05/2014, 16:25

... Dynamically induced finite bias anomalies in tunneling spectra . . . . 248 7.2 Dephasing and decoherence in quantum tunneling 258 7.2.1 VectorKeldyshmodelinthetimedomain 276 8 TUNNELING THROUGH MOVING ... surfaces and points, etc). Before turning to these artificially en- gineered devices, we will review in brief the origin of dynamical symmetry in ”nat- ural” quantum objects, i.e. in...

Ngày tải lên: 29/05/2014, 23:50

... Savasta Quantum effects in interacting electron systems: The role of spin in the interaction and entanglement in mesoscopic systems 307 1 Introduction 307 2 Introduction to spin and entanglement ... exchange coupling and scattering within N are assumed. Whatever subregion within the spacer, adjoining F L or F R , contains significant decaying exchange, or any interface-related scattering...

Ngày tải lên: 04/06/2014, 13:46