English
Related papers

Related papers: A hole-Cr$^{+}$ nano-magnet in a semiconductor qua…

200 papers

Transition metal ions provide a rich set of optically active defect spins in wide bandgap semiconductors. Chromium (Cr4+) in silicon-carbide (SiC) produces a spin-1 ground state with a narrow, spectrally isolated, spin-selective,…

We present a symmetry-based calculation of the electronic structure of a compound semiconductor quantum dot (QD) in the sp^3s* tight-binding model including the spin-orbit interaction. The Hamiltonian matrix is diagonalized exactly for CdTe…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 J. Perez-Conde , A. K. Bhattacharjee

Dilute magnetic semiconductors (DMS) are nonmagnetic semiconductors doped with magnetic transition metals. The recently discovered DMS material (Ba$_{1-x}$K$_{x}$)(Zn$_{1-y}$Mn$_{y}$)$_{2}$As$_{2}$ offers a unique and versatile control of…

Materials Science · Physics 2018-03-28 M. A. Surmach , B. J. Chen Z. Deng , C. Q. Jin , J. K. Glasbrenner , I. I. Mazin , A. Ivanov , D. S. Inosov

A (II,Mn)VI diluted magnetic semiconductor quantum dot with an integer number of electrons controlled with a gate voltage is considered. We show that a single conduction band electron is able to induce a spontaneous collective magnetization…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 J. Fernández-Rossier , L. Brey

Excitons in diluted magnetic semiconductors represent excellent probes for studying the magnetic properties of these materials. Various magneto-optical effects, which depend sensitively on the exchange interaction of the excitons with the…

The optic vibrational (confined and interface) modes and the electron-phonon and hole-phonon interactions are obtained, in the dielectric continuum model, for two diluted magnetic semiconductor structures: a single well of…

Materials Science · Physics 2009-10-31 X. F. Wang , I. C. da Cunha Lima , A. Troper

X-ray magnetic circular dichroism spectroscopy has been used to characterize the electronic structure and magnetic moment of Cr$_2^+$. Our results indicate that the removal of a single electron from the $4s\sigma_g$ bonding orbital of…

Semiconductor quantum dots with confined electron or hole spins show promise for quantum information processing as they allow for efficient electric field-driven qubit manipulation. However, their susceptibility to electric noise poses a…

Mesoscale and Nanoscale Physics · Physics 2024-08-08 Yaser Hajati , Guido Burkard

A review is given of advances in the field of carrier-controlled ferromagnetism in Mn-based diluted magnetic semiconductors and their nanostructures. Experimental results for III-V materials, where the Mn atoms introduce both spins and…

Materials Science · Physics 2015-06-24 Tomasz Dietl

We consider a semiconducting carbon nanotube (CNT) laying on a ferromagnetic insulating sub-strate with one end depassing the substrate and suspended over a metallic gate. We assume that the polarised substrate induces an exchange…

Mesoscale and Nanoscale Physics · Physics 2015-10-27 F. Pistolesi , R. Shekhter

A theory of electron spin relaxation in semiconducting carbon nanotubes is developed based on the hyperfine interaction with disordered nuclei spins I=1/2 of $^{13}$C isotopes. It is shown that strong radial confinement of electrons…

Materials Science · Physics 2009-11-11 Y. G. Semenov , K. W. Kim , G. J. Iafrate

We consider a mean-field approach to the hole-mediated ferromagnetism in III-V Mn-based semiconductor compounds to discuss the dependence of the hole density on that of Mn sites in Ga_{1-x}Mn_xAs. The hole concentration, p, as a function of…

Materials Science · Physics 2009-11-07 Raimundo R. dos Santos , Luiz E. Oliveira , J. d'Albuquerque e Castro

We use temporally resolved intensity cross-correlation measurements to identify the biexciton-exciton radiative cascades in a negatively charged QD. The polarization sensitive correlation measurements show unambiguously that the excited two…

Mesoscale and Nanoscale Physics · Physics 2014-02-11 Y. Benny , R. Presman , Y. Kodriano , E. Poem , D. Gershoni , T. A. Truong , P. M. Petroff

Molecular magnets are attractive as spin qubits due to their chemical tunability, addressability through electron-spin resonance techniques, and long coherence times. Clock transitions (CTs), for which the system is immune to the effect of…

We report magneto-photoluminescence studies of strongly quantum-confined "0-D" diluted magnetic semiconductors (DMS), realized in Mn$^{2+}$-doped ZnSe/CdSe core/shell colloidal nanocrystals. In marked contrast to their 3-D (bulk), 2-D…

Mesoscale and Nanoscale Physics · Physics 2012-06-21 R. Viswanatha , J. M. Pietryga , V. I. Klimov , S. A. Crooker

Spins in semiconductor quantum dots are promising local quantum memories to generate polarization-encoded photonic cluster states, as proposed in the pioneering Rudolph-Lindner scheme [1]. However, harnessing the polarization degree of…

Mesoscale and Nanoscale Physics · Physics 2023-11-28 N. Coste , M. Gundin , D. Fioretto , S. E. Thomas , C. Millet , E. Medhi , M. Gundin , N. Somaschi , M. Morassi , M. Pont , A. Lemaitre , N. Belabas , O. Krebs , L. Lanco , P. Senellart

It is well-known that the Curie temperature, and hence the magnetization, in diluted magnetic semiconductor (DMS) like Ga$_{1-x}$Mn$_x$As can be controlled by changing the equilibrium density of holes in the material. Here, we propose that…

Mesoscale and Nanoscale Physics · Physics 2010-05-04 L. Siddiqui , A. N. M. Zainuddin , S. Datta

The iron arsenide Sr2CrO3FeAs with the tetragonal Sr2GaO3CuS-type structure was synthesized and its crystal structure re-determined by neutron powder diffraction. In contrast to previous X-ray crystallographic studies, a mixed occupancy of…

Superconductivity · Physics 2010-02-24 Marcus Tegel , Franziska Hummel , Yixi Su , Tapan Chatterji , Michela Brunelli , Dirk Johrendt

We have performed x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) studies of the diluted ferromagnetic semiconductor Zn$_{1-\textit{x}}$Cr$_\textit{x}$Te doped with iodine (I) or nitrogen (N), corresponding…

A mean field model of ferromagnetism mediated by delocalized or weakly localized holes in zinc-blende and wurzite diluted magnetic semiconductors is presented. The model takes into account: (i) strong spin-orbit and kp couplings in the…

Materials Science · Physics 2009-10-31 T. Dietl , H. Ohno , F. Matsukura