Library

X
Your search history is empty.
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Improved performance of magnetically tunable GaAs and InP far-infrared detectors (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 72 (1992), S. 680-683 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Properties of GaAs and InP magnetically tunable far-infrared (FIR) detectors based on transitions between 1s-2p(+/0/−) shallow donor states, were studied in magnetic fields up to 8 T. Repeatable low background radiation conditions were obtained by using cyclotron emission from InSb and GaAs as a FIR source. Signal and noise dependence on the temperature, electric, and magnetic fields was investigated. Physical mechanisms responsible for the signal and noise dependencies on the temperature, electric, and magnetic fields are discussed. Local generation-recombination instabilities are proposed as a physical mechanism causing appearance of the low frequency noise in high magnetic fields.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.351852
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    High magnetic field studies of two-dimensional electron gas in a GaN/GaAlN heterostructure: Mechanisms of parallel conduction (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 1251-1255 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report on quantum Hall effect (QHE) and Shubnikov–de-Haas (SdH) measurements for a GaN/GaAlN heterostructure in high magnetic fields (up to 35 T). The observed well defined SdH oscillations, correlated with QHE plateaus, confirm the existence of a two-dimensional electron gas at the GaN/GaAlN interface. The Shubnikov–de-Haas oscillations are superimposed on a strong positive magnetoresistance. We show that this positive magnetoresistance can be linked to a parallel conduction channel. The analysis of the high magnetic field data yields information about the carrier concentration and mobility in this channel. The concentration and mobility of two-dimensional gas and the parallel conduction layer are analyzed in a wide temperature range (1.9–77 K). A physical model (based on the band diagram and mobility calculations) explaining the origin of parallel conduction is presented. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1328788
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    A far-infrared spectrometer based on cyclotron resonance emission sources (1992)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 63 (1992), S. 3293-3297 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Practical realization of the spectrometer based on the cyclotron emission sources is presented. It is shown that it can be used for transmission measurements in the range from 35 to 110 cm−1 with resolution up to 1.3 cm−1. Performances of the spectrometer are demonstrated by its application to the studies of impurity and free-electron states in two-dimensional structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1142540
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Determination of the effective mass of GaN from infrared reflectivity and Hall effect (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 68 (1996), S. 1114-1116 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Infrared reflectivity and Hall effect measurements were performed on highly conducting n-type GaN (n≈6×1019 cm−3) bulk crystals grown by the high-pressure high-temperature method. Values of electron-plasma frequency and free-electron concentration were determined for each sample of the set of seven crystals. It enabled us to calculate the perpendicular effective mass of electrons in the wurtzite structure of GaN as m*=0.22±0.02 m0. Effects of nonparabolicity and a difference between parallel and perpendicular components of the effective mass are small and do not exceed the experimental error. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.115730
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Far infrared spectroscopy with high resolution cyclotron resonance filters (1998)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 84 (1998), S. 433-438 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A new type of far infrared spectroscopy based on a cyclotron resonance notch filter is demonstrated. The resonant absorption energy of such a filter is tuned by an external magnetic field. GaAs/AlGaAs heterostructures with high mobility two-dimensional electron gas are used to obtain an optimal cyclotron resonance filter. With such a filter, we can analyze far infrared radiation in the range 40–150 cm−1 with a resolution of up to 2 cm−1. A procedure for the determination of the spectral characteristics of an unknown source from the detector signal is presented. We show that the cyclotron-resonance-notch-filter based spectrometer provides ultralow background radiation conditions for measurements. We also demonstrate the performance of the spectrometer by an analysis of electrostimulated far infrared emission of InSb, GaAs bulk crystals as well as of selectively doped quantum wells. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.368081
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Investigation of longitudinal-optical phonon-plasmon coupled modes in highly conducting bulk GaN (1995)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 67 (1995), S. 2524-2526 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report a cross-correlated investigation, performed by means of Raman scattering and infrared spectroscopy, of coupled LO phonon-plasmon modes in bulk GaN. Using different samples with different (high) residual concentrations of free carriers, we find that the high-energy Raman mode follows closely the plasma frequency resolved from the infrared data. On the opposite, the low-frequency modes appears down shifted, with respect to the standard TO phonon frequency, by about 11 cm−1. Both findings agree satisfactorily with predictions of the linear response theory for undamped phonon-plasmon modes and establish Raman scattering as a powerful and nondestructive tool to investigate the residual doping level of GaN up to about 1020 cm−3 . © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.114446
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Effective g* factor of two-dimensional electrons in GaN/AlGaN heterojunctions (1999)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 75 (1999), S. 3156-3158 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The conduction band parameters of two-dimensional (2D) electrons in high density GaN/AlGaN heterojunctions were studied using the cyclotron resonance and magnetotransport techniques in high magnetic fields (24 T) and low temperatures (300 mK). The Landau level splitting determined from the cyclotron resonance experiment yielded the effective mass of 2D carriers, m*=0.242±0.002 m0. The Lande g factor for the 2D electrons (g=2.06±0.04) was determined from the angular dependence of the amplitude of Shubnikov–de-Haas oscillations experiments in tilted magnetic field. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.125262
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Cyclotron resonance and quantum Hall effect studies of the two-dimensional electron gas confined at the GaN/AlGaN interface (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 70 (1997), S. 2123-2125 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report on high magnetic fields (up to 40 T) cyclotron resonance, quantum Hall effect and Shubnikov-de-Hass measurements in high frequency transistors based on Si-doped GaN–AlGaN heterojunctions. A simple way of precise modelling of the cyclotron absorption in these heterojunctions is presented. We clearly establish two-dimensional electrons to be the dominant conducting carriers and determine precisely their in-plane effective mass to be 0.230±0.005 of the free electron effective mass. The increase of the effective mass with an increase of two-dimensional carrier density is observed and explained by the nonparabolicity effect. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.118967
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Investigation of optically active E1 transversal optic phonon modes in AlxGa1−xN layers deposited on 6H–SiC substrates using infrared reflectance (1998)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 73 (1998), S. 1760-1762 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report an investigation, performed in the full composition range x=0–1, of the change in infrared reflectivity spectra of AlxGa1−xN layers deposited on 6H–SiC substrates. We have found two different transverse E1(TO) phonon frequencies that can be assigned to AlN-like and GaN-like modes. The composition dependences of these frequencies can be well approximated by linear functions and the oscillator strengths scale like the corresponding Al and Ga mole fractions, respectively. On a purely experimental basis, this establishes evidence of a two-mode behavior for this controversial alloy system. The frequencies of the impurity mode of Ga in AlN (622 cm−1) and of the impurity mode of Al in GaN (643 cm−1) were determined. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.122273
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Acoustic phonon scattering of two-dimensional electrons in GaN/AlGaN heterostructures (2002)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 80 (2002), S. 1228-1230 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have measured the temperature dependence of the mobility of the two-dimensional electron gas in AlGaN/GaN heterostructures grown on bulk GaN substrates. The linear dependence of the inverse mobility on temperature at temperatures below 50 K indicates the importance of acoustic phonon scattering in these high mobility heterostructures. Using the temperature dependence of the mobility at a range of carrier densities, we determined the GaN conduction band deformation potential to be ac=9.1±0.7 eV. This result provides a crucial parameter for accurate calculations of intrinsic mobility limits in AlGaN/GaN heterostructures. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1448401
    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...