ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
  • Articles  (270)
Collection
Source
Publisher
Years
Journal
Topic
  • 1
    Electronic Resource
    Electronic Resource
    Line broadening, line shifting, and line coupling effects on N2–H2O stimulated Raman spectra (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 91 (1989), S. 5916-5925 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: In order to understand the influence of H2O on the stimulated Raman Q-branch spectra of nitrogen in combusting media, an exhaustive theoretical and experimental study has been carried out. Starting from a semiclassical model, particularly convenient at high temperature, the Q-line broadening and shifting coefficients have been calculated over a wide temperature range and for a large number of lines. Stimulated Raman Spectra (SRS) measurements have allowed us to test these calculated line broadening coefficients and thus establish the high accuracy of semiclassical values. The theoretical broadening coefficients have been inverted to deduce state-to-state rotational relaxation rates by using two types of fitting laws. A partial test of the resulting Q-branch profiles has been realized at moderate pressures leading to a discrimination between these two laws. Furthermore, the effect of rotational energy transfers on collisionally narrowed profiles at higher densities has been simulated and compared with the pure N2 case.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.457461
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Collision-induced population transfer in infrared absorption spectra. III. Temperature dependence of absorption in the Ar-broadened wing of CO2 ν3 band (1990)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 93 (1990), S. 2217-2221 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We present experimental and theoretical results on the absorption in the Ar-broadened wing of the infrared CO2 ν3 band. Measurements have been made in the 293–765 K temperature range for total gas pressures up to 60 bar and are in good agreement with previous determinations at room temperature. Calculations have been carried out by using a line by line coupling theory presented and tested previously [J. Chem. Phys. 89, 625 (1988) and 91, 2163 (1989)]. The theoretical approach accounts for both line mixing and the wave-number dependence of the relaxation operator. It enables correct modeling of the temperature dependence of absorption. The strong sublorentzian absorption resulting from competitions between negative and positive individual line contributions is analyzed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.459054
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Measurements and calculations of CO2 room-temperature high-pressure spectra in the 4.3 μm region (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 90 (1989), S. 2944-2950 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Measurements of the absorption by pure CO2 in the 4.3 μm region are presented. They refer to the temperature of 291 K and densities in the 1–80 amagat range. Calculations based on the addition of Lorentzian contributions strongly overestimate the absorption since they do not account for line overlapping. The energy corrected sudden approximation (ECSA) is used to model line mixing within the impact approximation. The scaling parameters of this model are deduced from line-broadening data. This calculation strongly underestimates the absorption in the spectral region near the edges of the vibrational band, whereas it overestimates the absorption in the far wings of the lines. This is attributed to the impact approximation which does not account for the frequency dependence of the relaxation operator. This dependence is roughly determined from our results; it is in good qualitative agreement with the few corresponding available results.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.455894
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    X-ray standing wave study of MnTe fractional monolayers inserted in CdTe (001) (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 88 (2000), S. 4889-4897 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The x-ray standing wave method is used in correlation with reflection high-energy electron diffraction and scanning tunneling microscopy to investigate the crystallographic features of MnTe monolayers inserted in CdTe (001). Either conventional molecular beam epitaxy or atomic layer epitaxy were employed for the formation of the CdTe starting surface, the deposition of the MnTe fractional monolayer, and its encapsulation by CdTe. Significant differences concerning the ratio of Mn atoms involved in MnTe clusters to those incorporated as part of a CdMnTe alloy are observed between the samples. Those differences are due to differing CdTe starting surface roughness. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1311829
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    State-to-state rotational cross sections in vibrational modes. Application to the infrared Q-branch profile for the (11 10)I←(00 00) 12C16O2 bending band (1993)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 98 (1993), S. 3747-3753 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Direct connection between spectroscopic relaxation cross sections and appropriate state-to-state rotational cross sections in vibrational modes enables one to introduce convenient energy corrections to the sudden approximation. Since the angular momentum coupling photon–rotation–vibration is properly taken into account, this approach applies to stretching as well as bending bands. Diode laser experiments have been made for pure 12C16O2 in the infrared Q branch of the (11 10)I←(00 00) band in order to investigate the effect of collisional line mixing on the spectral profile. The energy corrected sudden scaling law is used within the present theoretical approach for both the inversion of j→0 basis cross sections from broadening data and the calculation of line-coupling coefficients. Resulting absorption profiles are in good agreement with measured values without the need for the introduction of any ad hoc decoupling factor for the considered bending band.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.464053
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Atomic layer epitaxy and molecular beam epitaxy of CdTe/MnTe superlattices: A structural and optical study (1998)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 84 (1998), S. 4300-4308 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Atomic layer epitaxy (ALE) is investigated together with conventional molecular beam epitaxy (MBE) for the growth of CdTe/MnTe superlattices. A systematic structural and magneto-optical study demonstrates that: (i) all Mn atoms incident on the surface get incorporated; however, when a quantity superior or equal to 1 monolayer of Mn is sent onto the surface per ALE cycle, the growth front roughens, leading to the formation of MnTe islands, (ii) optimized atomic layer epitaxy allows us to obtain at 280 °C CdTe/MnTe superlattices with a better control than in conventional MBE, but does not prevent the exchange between Cd and Mn atoms from occurring at the interfaces, (iii) low temperature ALE (200 °C and lower) seems to be a promising way of obtaining more abrupt interfaces. A precise value of the ratio of the elastic coefficients 2c12/c11 is otherwise inferred through this study for zincblende MnTe (1.12). © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.368648
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Atomic layer epitaxy of CdTe and MnTe (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 3035-3041 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Atomic deposition techniques are investigated for binary semiconductors of the telluride family, namely CdTe and MnTe. An original method for directly determining the CdTe atomic layer epitaxy (ALE) growth rate—in monolayers/cycle—is proposed, consisting in monitoring the reflection high-energy electron diffraction (RHEED) sublimation intensity oscillations of an ALE grown CdTe layer deposited on a MgTe buffer layer. The ALE CdTe autoregulated growth rate at 0.5 monolayer/cycle (in the substrate temperature domain between 260 and 290 °C) is accounted for on the basis of an atomic model which relies on the alternating c(2×2) Cd and (2×1) Te surface reconstructions during the ALE cycle. RHEED studies on MnTe atomic deposition, together with x-ray diffraction and transmission electron microscopy on ALE grown CdTe/MnTe superlattices reveal that all deposited Mn atoms are incorporated so that no autoregulated growth can be achieved. Furthermore, less than one or just one monolayer of Mn must be sent on the surface per ALE cycle to obtain well controlled superlattices with abrupt interfaces. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.361243
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    CdTe/MgTe heterostructures: Growth by atomic layer epitaxy and determination of MgTe parameters (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 80 (1996), S. 6257-6265 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Atomic layer epitaxy (ALE) is investigated for the binary semiconductor MgTe. Reflection high-energy electron-diffraction studies on MgTe atomic deposition, together with x-ray diffraction, high-resolution transmission electron microscopy, and photoluminescence experiments on ALE-grown CdTe/MgTe superlattices are reported. They reveal that an autoregulated growth at 0.7±0.1 MgTe monolayer/ALE cycle can be achieved in a substrate temperature range between 260 and 300°C. New values of the zinc-blende MgTe lattice parameter, aMgTe=6.420 ±0.005 A(ring), of the ratio of the elastic coefficients 2c12c11 (MgTe)=1.06, and of the 300 K MgTe band gap, EG=3.5 eV, are obtained by correlating x-ray-diffraction and optical results. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.363714
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Quantitative interfacial profiles in CdTe/Mn(Mg)Te heterostructures (1998)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 84 (1998), S. 756-764 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have measured by high resolution transmission electron microscopy (HRTEM) the width of interfaces in two II–VI heterostructures: CdTe/MnTe and CdTe/MgTe, as a function of the growth mode. A critical review of the different parameters involved in the direct determination of the chemical profile by HRTEM enables us to precisely determine the sensitivity and accuracy of the methods on these particular materials. The measured interface width is of the order of 2.5–3 monolayers (ML) and is compatible with an exchange mechanism involving the monolayer being grown and the last deposited monolayer. Several growth procedures were compared: conventional molecular beam epitaxy and atomic layer epitaxy (ALE). In the case of saturated and oversaturated ALE the inverse MnTe/CdTe interface is no longer planar. A destabilization of the growth front occurs when one or more Mn monolayers per cycle are deposited, through the formation of MnTe islands. Thermal interdiffusion seems to be negligible in the case of Mn. The present HRTEM values for the interface widths extend the results obtained by magneto-optical measurements to higher concentration values and confirm the exchange mechanism. The higher value obtained by x-ray reflectivity (4.7 ML) is explained by the large difference of the average volume on which the measurement is performed. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.368134
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Interface dilution and morphology of CdTe/MnTe superlattices studied by small- and large-angle x-ray scattering (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 87 (2000), S. 7266-7274 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have performed small- and large-angle x-ray scattering experiments on CdTe/MnTe superlattices. The Fresnel optical method and the distorted wave Born approximation were used to extract from small-angle measurements out-of-plane and in-plane information about the interfaces. Specular reflectivity shows that the interface roughness is quite high (about 7 Å) for all superlattices. The effective MnTe concentration, directly determined from the refractive index profile, is successfully used to simulate the structured nonspecular scattering, and to determine the lateral correlation length of the interface roughness (about 1500±750 Å). Moreover, it is shown that the layers are almost completely correlated over the sample thickness. The thickness fluctuations along the growth direction are estimated from the analysis of the large-angle (004) reflection, and the effective MnTe profile is also checked by dynamical simulation. It is shown that the small- and large-angle results are in good agreement. The MnTe profile width deduced from x-ray reflectivity is slightly overestimated due to the large integration area of this technique. An estimation of the local MnTe profile is given. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.372979
    Location Call Number Expected 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...