Experimental quasiparticle dynamics in a superconducting, imaging x-ray spectrometer

Applied Physics Letters

Volumn 71, Issue 26, 1997, Pages 3901-3903

  Friedrich, S ^a   Segall, K ^a   Gaidis, M C ^a,c   Wilson, C M ^a   Prober, D E ^a   Szymkowiak, A E ^b   Moseley, S H ^b  

^a Yale University   (United States)

^b NASA GODDARD SPACE FLIGHT CENTER   (United States)

^c CALIFORNIA INSTITUTE OF TECHNOLOGY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CALCULATIONS; ELECTRON SCATTERING; ELECTRON TUNNELING; MATHEMATICAL MODELS; PHOTODETECTORS; PHOTONS; RELAXATION PROCESSES; SUPERCONDUCTING DEVICES; X RAYS;

QUASIPARTICLE DYNAMICS;

X RAY SPECTROMETERS;

EID: 0031379529     PISSN: 00036951     EISSN: None     Source Type: Journal    
DOI: 10.1063/1.120538     Document Type: Article

References (17)

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2. S. Friedrich, K. Segall, M. C. Gaidis, C. M. Wilson, D. E. Prober, P. J. Kindlmann, A. E. Szymkowiak, and S. H. Moseley, IEEE Trans. Appl. Supercond. 7, 3383 (1997).
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6. S. Friedrich, K. Segall, D. Toledano, D. E. Prober, A. E. Szymkowiak, and S. H. Moseley, Nucl. Instrum. Methods Phys. Res. A 370, 44 (1996); M. C. Gaidis, S. Friedrich, D. E. Prober, A. E. Szymkowiak, and S. H. Moseley, J. Low Temp. Phys. 93, 603 (1993).
7. S. Friedrich, K. Segall, D. Toledano, D. E. Prober, A. E. Szymkowiak, and S. H. Moseley, Nucl. Instrum. Methods Phys. Res. A 370, 44 (1996); M. C. Gaidis, S. Friedrich, D. E. Prober, A. E. Szymkowiak, and S. H. Moseley, J. Low Temp. Phys. 93, 603 (1993).
8. S. Friedrich, Ph.D. thesis, Yale University, 1997.
9. The points at lower energy in Fig. 1 are due to substrate absorptions.
10. J. Jochum, H. Kraus, M. Gutsche, B. Kemmather, F. V. Freilitzsch, and R. L. Mossbauer, Ann. Phys. (Leipzig) 2, 611 (1993).
11. We divide up the energies in the trap/counter electrode into bins of 10 μV and calculate the number of quasiparticles entering/leaving each bin through inelastic scattering, tunneling, recombination or outdiffusion. Both scattering and tunneling rates are energy dependent (see Refs. 6, 7, 11, and 14).
12. The tunneling time in the normal state is calculated from the resistivity of the barrier. In the superconducting state, the tunnel time is shorter for quasiparticle energies near the gap edge because of the larger density of states (see Ref. 8). This is accounted for in the model.
13. 2] relates the resistivity, ρ, to the diffusion constant with a minimum number of band-structure dependent quantities; n(Ef) is the density of states at the Fermi surface.
14. V. Narayanamurti, R. C. Dynes, P. Hu, H. Smith, and W. F. Brinkman, Phys. Rev. B 18, 6041 (1978).
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16. There is a second process, called back tunneling, which gives a current in the forward direction: a pair splits in the trap, and coherently one electron from that pair forms a pair in the counter electrode. Here also there is a reverse process which cancels the forward current at low voltage.
17. Our present devices are limited to the voltage range V<90 μV by Fiske modes. With a smaller junction length, biasing at higher voltages will be easily accomplished.