Electronic structure and Fermi surface of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">CrO</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>

Brener, N. E.; Tyler, John M.; Callaway, Joseph; Bagayoko, Diola; Zhao, Guoxia

doi:10.1103/physrevb.61.16582

Cited by 47 publications

(27 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results given above point out the necessity of strongly spin-polarized ferromagnets for the proper operation of a SF refrigerator. Among the predicted halfmetallic candidates it is possible to use CrO 2 ͑Schwartz, 1986; Kämper et al, 1987;Brener et al, 2000͒, for which values of P in the range 85-100 % have been reported ͑Coey et al, 1998;Ji et al, 2001;Dedkov et al, 2002;Parker et al, 2002͒, …”

Section: Sf Systemsmentioning

confidence: 99%

Opportunities for mesoscopics in thermometry and refrigeration: Physics and applications

et al. 2006

View full text Add to dashboard Cite

This review presents an overview of the thermal properties of mesoscopic structures. The discussion is based on the concept of electron energy distribution, and, in particular, on controlling and probing it. The temperature of an electron gas is determined by this distribution: refrigeration is equivalent to narrowing it, and thermometry is probing its convolution with a function characterizing the measuring device. Temperature exists, strictly speaking, only in quasiequilibrium in which the distribution follows the Fermi-Dirac form. Interesting nonequilibrium deviations can occur due to slow relaxation rates of the electrons, e.g., among themselves or with lattice phonons. Observation and applications of nonequilibrium phenomena are also discussed. The focus in this paper is at low temperatures, primarily below 4 K, where physical phenomena on mesoscopic scales and hybrid combinations of various types of materials, e.g., superconductors, normal metals, insulators, and doped semiconductors, open up a rich variety of device concepts. This review starts with an introduction to theoretical concepts and experimental results on thermal properties of mesoscopic structures. Then thermometry and refrigeration are examined with an emphasis on experiments. An immediate application of solid-state refrigeration and thermometry is in ultrasensitive radiation detection, which is discussed in depth. This review concludes with a summary of pertinent fabrication methods of presented devices.

show abstract

Section: Sf Systemsmentioning

confidence: 99%

Opportunities for mesoscopics in thermometry and refrigeration: Physics and applications

et al. 2006

View full text Add to dashboard Cite

show abstract

“…[8][9][10] In particular, some ZB structure transition metal chalcogenides and pnictides have been predicted to be HM ferromagnets on the basis of theoretical calculations. [11][12][13][14][15][16][17][18][19][20][21][22][23] Here the magnetic properties of the transition metal matrix is modified via the hybridization between the transition metal 3-d and the s and p orbitals of the pinctogen or the chalcogen. Half-metallicity arises as a result of interplay between the exchange splitting and the hybridization.…”

Section: Half-metallic (Hm) Ferromagnetismmentioning

confidence: 99%

First-principles theoretical studies of half-metallic ferromagnetism in CrTe

2010

View full text Add to dashboard Cite

Using full-potential linear augmented plane wave method (FP-LAPW) and the density functional theory, we have carried out a systematic investigation of the electronic, magnetic, and cohesive properties of the chalcogenide CrTe in three competing structures: rock-salt (RS), zinc blende (ZB) and the NiAs-type (NA) hexagonal. Although the ground state is of NA structure, RS and ZB are interesting in that these fcc-based structures, which can possibly be grown on many semiconductor substrates, exhibit half-metallic phases above some critical values of the lattice parameter. We find that the NA structure is not half-metallic at its equilibrium volume, while both ZB and RS structures are. The RS structure is more stable than the ZB, with an energy that is lower by 0.25 eV/atom. While confirming previous results on the half-metallic phase in ZB structure, we provide hitherto unreported results on the half-metallic RS phase, with a gap in the minority channel and a magnetic moment of 4.0 µB per formula unit. A comparison of total energies for the ferromagnetic (FM), nonmagnetic (NM), and antiferromagnetic (AFM) configurations shows the lowest energy configuration to be FM for CrTe in all the three structures. The FP-LAPW calculations are supplemented by linear muffin-tin orbital (LMTO) calculations using both local density approximation (LDA) and LDA+U method. The exchange interactions and the Curie temperatures calculated via the linear response method in ZB and RS CrTe are compared over a wide range of the lattice parameter. The calculated Curie temperatures for the RS phase are consistently higher than those for the ZB phase.

show abstract

“…1,18,34,35,37 As the partial densities of states ͑PDOS͒ were previously reported for the LSDA and LSDAϩU exchange-correlation functionals, we present here only the PDOS obtained with the GGA functional. In Fig.…”

Section: A Bonding and Partial Densities Of Statesmentioning

confidence: 99%

Electronic structure ofCrO2as deduced from its magneto-optical Kerr spectra

et al. 2002

View full text Add to dashboard Cite

We report a combined experimental-computational investigation of the electronic structure of CrO 2 . We have measured the magneto-optical Kerr spectra of CrO 2 at 10 K and 300 K. At 10 K the Kerr signal is significantly enhanced over that obtained at 300 K. We compare the measured Kerr spectra to first-principles theoretical spectra, which we computed using three different approximations to the exchange-correlation functional, i.e., the local spin-density approximation ͑LSDA͒, generalized gradient approximation ͑GGA͒, and LSDAϩU. The experimental low-temperature magneto-optical Kerr spectra are best explained by calculations employing the GGA functional. The addition of an on-site Coulomb correlation U does not lead to reasonable Kerr spectra.

show abstract

Electronic structure and Fermi surface ofCrO2

Cited by 47 publications

References 13 publications

Opportunities for mesoscopics in thermometry and refrigeration: Physics and applications

Opportunities for mesoscopics in thermometry and refrigeration: Physics and applications

First-principles theoretical studies of half-metallic ferromagnetism in CrTe

Electronic structure ofCrO2as deduced from its magneto-optical Kerr spectra

Contact Info

Product

Resources

About