Multi-quantum-wire strained lasers are reported in the Ga, -,In.tAs/Ga, -.,Al,As semiconductor material system with a minimum threshold current of IX8 ,xA and maximum powers of =50 PW in continuous multimode operation at wavelengths of -=4RO nm and differential output of =0.5 ,LLW/ ,uA. The structures, fabricated by molecular-beam epitaxy, are self-aligned, self-isolated, and minimize electrica...

Highly sensitive and fast photodetectors can enable low power, high bandwidth on-chip optical interconnects for silicon integrated electronics. III-V compound semiconductor direct-bandgap materials with high absorption coefficients are particularly promising for photodetection in energy-efficient optical links because of the potential to scale down the absorber size, and the resulting capacitan...

The realization and detection of Majorana fermions in condensed matter systems are of considerable importance and interest. We propose a scheme to detect the Majorana fermions by Fano resonance in hybrid nanostructures made of semiconductor quantum dots and quantum wire in proximity to superconductor. Through detailed theoretical studies of the transport properties of our hybrid nanostructures ...

The electronic structure and binding energy of a hydrogenic acceptor impurity in 2, 1, and 0-dimensional semiconductor nano-structures (i.e. quantum well (QW), quantum well wire (QWW), and quantum dot (QD)) are studied in the framework of effective-mass envelopefunction theory. The results show that (1) the energy levels monotonically decrease as the quantum confinement sizes increase; (2) the ...

We introduce the spinand momentum-dependent force operator, which is defined by the Hamiltonian of a clean semiconductor quantum wire with homogeneous Rashba spin-orbit SO coupling attached to two ideal i.e., free of spin and charge interactions leads. Its expectation value in the spin-polarized electronic wave packet injected through the leads explains why the center of the packet gets deflect...

In this paper, using the tight-binding model, we extend the real-space renormalization group method to time-dependent Hamiltonians. We drive the time-dependent recursion relations for the renormalized tight-binding Hamiltonian by decimating selective sites of lattice iteratively. The formalism is then used for the calculation of the local density of electronic states for a one dimensional quant...

We have calculated the optical absorption spectra of magnetoexcitons in T-wire semiconductor. It is calculated using the semiconductor Bloch equations in time and real-space domains. The peak and the linewitdth of the fundamental exciton transition are investigated as a function of the applied magnetic and static electric field. The latter is applied along the wire axis and induces a broadening...

Recent observation of zero bias conductance peaks in semiconductor wire/superconductor heterostructures has generated great interest, and it is in hot debate if the observation is associated with Majorana fermions (MFs). Here we study the local and crossed Andreev reflections in a junction of two normal leads and a sand­ wiched superconductor­ semiconductor wire with two spatially separated but...