Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1990-1994  (6)
Source
Material
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Line-shape analysis of reflectance spectra from ZnSe/Zn0.99Fe0.01Se spin superlattices (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 2988-2991 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Line-shape analysis of magnetoreflectance spectra from ZnSe/Zn0.99Fe0.01Se quantum well structures was performed using a classical dielectric function model. This model explains the spectral dependence on the sample geometry, as well as providing additional evidence of spin superlattice formation in ZnSe/ZnFeSe heterostructures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356195
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Optical study of strained ZnSe/GaAs and ZnMnSe/GaAs epilayers (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 2936-2940 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We studied strain-induced band splittings of ZnSe/GaAs and Zn1−xMnxSe/GaAs epilayers of 0.064–3 μm thickness by reflectance and polarized photoluminescence. Polarized photolumi- nescence was found particularly useful in optical transition identification. The spectacular difference in magnetic field sensitivity of heavy hole and light hole exciton in ZnMnSe is also very helpful in transition identification. The evaluated heavy-light hole band splitting is in general accordance with previous data. An exceptionally strong variation of the strain with epilayer thickness is observed in the thickness range 0.5–2 μm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356188
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Spin lifetimes in diluted magnetic semiconductor spin superlattices : 37th Annual conference on magnetism and magnetic materials (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 6051-6053 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The growth of spin superlattice structures in which spin-up and spin-down carriers occupy alternating layers in the structure has recently been reported. We report here measurements of electron and hole spin lifetimes and spin relaxation processes. In dc photoluminescence spectra, both the higher-energy (+1/2,+3/2) and lower-energy (−1/2,−3/2) heavy-hole exciton interband transitions are observed, even though it would be energetically favorable for the spin-up carriers to first relax to the spin-down state before radiative recombination. From the field dependence of the intensity ratios of these components and a rate equation model, we determine the heavy hole τhs and electron τes spin lifetimes relative to the radiative lifetime τr, with τhs/τr≈4.5 and τes/τr≈0.08, so that the heavy-hole spin lifetime is ≈50 times longer than that of the electron. This is attributed to the strain-induced splitting of the heavy- and light-hole bands, which prevents fast spin relaxation of the holes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.353466
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Spin-polarized carrier populations in diluted magnetic semiconductor quantum well structures (abstract) : The 5th Joint MMM−Intermag Conference (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 70 (1991), S. 6413-6413 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Diluted magnetic semiconductors (DMS) offer the opportunity to significantly alter heterojunction band offsets via an applied magnetic field due to the large Zeeman splittings (enhanced g-factors) they exhibit. We have previously reported field-dependent spatial spin segregation of holes in DMS quantum well structures1,2 which resulted from the small band offset and large spin splitting exhibited by the valence band. We report here the growth of tailored Zn1−xFexSe/ZnSe quantum well structures in which both electrons and holes are spatially segregated according to their spin, resulting in spin-polarized carrier populations in the barriers and wells: the spin-down carriers are localized in the Zn1−xFexSe barriers, while the spin-up carriers are localized in the wells. Both single and multiple quantum well samples were grown by molecular-beam epitaxy on GaAs(001) substrates with 100 A(ring) barriers and wells. The heavy-hole excitonic transitions were studied with magnetoreflectivity at T=4.2 K and fields up to 8 T. The magnetoreflectivity data show that both (−3/2→−1/2) and (3/2→1/2) excitonic transitions are of equal intensity and spatially direct (type I), with the former showing the strong field dependence expected for localization in the magnetically active barriers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.349912
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Spin separation in diluted magnetic semiconductor quantum well systems (invited) : 35th annual conference on magnetism and magnetic materials San Diego, California (USA) 29 Oct − 1 Nov 1990 (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 6097-6102 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Heterostructures containing diluted magnetic semiconductor (DMS) layers offer the possibility of magnetically tuning the heterojunction band alignment due to the extraordinarily large spin-splitting of the DMS bands (large effective g-factor). This field-dependent band alignment has significant consequences for spin-dependent carrier confinement as evidenced in magnetooptic or magneto-transport experiments. We have examined two wide-gap DMS quantum well systems in which the band alignment is dominated by the DMS spin-splitting rather than by the more commonly observed effects of differences in bandgap, natural band offset, and strain. Quantum well structures with (Zn,Fe)Se or (Zn,Mn)Se barriers and ZnSe wells have been grown to investigate magnetically tuned, spin-dependent quantum confinement. In these systems, the band offset appears almost entirely in the conduction band, so that the electrons are confined to the ZnSe wells. However, the hole confinement is continuously tunable by an external magnetic field applied normal to the layer plane, since the valence band spin-splitting is approximately an order of magnitude larger at modest fields (1 T) than the zero field VB offset. This produces a field-induced spin dependent type I/type II band alignment and a consequent spatial spin separation of the holes. The quantum well structure exhibits a type I "straddling'' alignment for the mj=+3/2 level, with the spin "up'' holes localized in the ZnSe wells, and a type II "staggered'' alignment for the mj=−3/2 level in which the spin "down'' holes are localized in the barriers. The observed exciton splittings, intensities and temperature dependence are consistent with this model. In the Zn0.91Mn0.09Se/ZnSe system, a second bound state is observed in the conduction band in the σ− polarization in magnetoreflectivity measurements. A quantitative fit to the data yields a value of approximately 1 meV for the zero field valence band offset. These systems represent the first DMS-based heterostructures in which such field-dependent confinement has been observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347779
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Molecular beam epitaxy of a low strain II-VI heterostructure: ZnTe/CdSe (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 58 (1991), S. 1783-1785 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report the growth of a new closely lattice-matched II-VI heterostructure: ZnTe/CdSe (Δa/a∼0.3%). Epilayers of zinc blende CdSe grown on ZnTe buffer layers are shown to have much better quality than those grown earlier (with a 7% mismatch) on GaAs substrates. This permitted the first successful growth of high quality superlattices of ZnTe/CdSe. The superlattices were studied by x-ray diffraction, transmission electron microscopy, and optical techniques. Results of photoluminescence and optical transmission measurements show that ZnTe/CdSe superlattices have a very small valence-band offset.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.105090
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...