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Title: Integrated semiconductor quantum dot scintillation detector: Ultimate limit for speed and light yield

Abstract

Here, a picosecond-range timing of charged particles and photons is a long-standing challenge for many high-energy physics, biophysics, medical and security applications. We present a design, technological pathway and challenges, and some properties important for realization of an ultrafast high-efficient room-temperature semiconductor scintillator based on self-assembled InAs quantum dots (QD) embedded in a GaAs matrix. Low QD density (<; 10 15 cm -3), fast (~5 ps) electron capture, luminescence peak redshifted by 0.2-0.3 eV from GaAs absorption edge with fast decay time (0.5-1 ns) along with the efficient energy transfer in the GaAs matrix (4.2 eV/pair) allows for fabrication of a semiconductor scintillator with the unsurpassed performance parameters. The major technological challenge is fabrication of a large volume (> 1 cm 3 ) of epitaxial QD medium. This requires multiple film separation and bonding, likely using separate epitaxial films as waveguides for improved light coupling. Compared to traditional inorganic scintillators, the semiconductor-QD based scintillators could have about 5x higher light yield and 20x faster decay time, opening a way to gamma detectors with the energy resolution better than 1% and sustaining counting rates MHz. Picosecond-scale timing requires segmented low-capacitance photodiodes integrated with the scintillator. For photons, the proposed detector inherentlymore » provides the depth-of-interaction information.« less

Authors:
 [1];  [1];  [1];  [2]
  1. SUNY Colleges of Nanoscale Science and Engineering, Albany, NY (United States)
  2. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1262337
Report Number(s):
FERMILAB-PUB-16-241-PPD
Journal ID: ISSN 0018-9499; 1466588
Grant/Contract Number:
AC02-07CH11359
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
IEEE Transactions on Nuclear Science
Additional Journal Information:
Journal Volume: 63; Journal Issue: 2; Journal ID: ISSN 0018-9499
Publisher:
Institute of Electrical and Electronics Engineers (IEEE)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; optical waveguides; quantum dots; semiconductor radiation detectors; solid scintillation detectors

Citation Formats

Oktyabrsky, Serge, Yakimov, Michael, Tokranov, Vadim, and Murat, Pavel. Integrated semiconductor quantum dot scintillation detector: Ultimate limit for speed and light yield. United States: N. p., 2016. Web. doi:10.1109/TNS.2015.2502426.
Oktyabrsky, Serge, Yakimov, Michael, Tokranov, Vadim, & Murat, Pavel. Integrated semiconductor quantum dot scintillation detector: Ultimate limit for speed and light yield. United States. doi:10.1109/TNS.2015.2502426.
Oktyabrsky, Serge, Yakimov, Michael, Tokranov, Vadim, and Murat, Pavel. Wed . "Integrated semiconductor quantum dot scintillation detector: Ultimate limit for speed and light yield". United States. doi:10.1109/TNS.2015.2502426. https://www.osti.gov/servlets/purl/1262337.
@article{osti_1262337,
title = {Integrated semiconductor quantum dot scintillation detector: Ultimate limit for speed and light yield},
author = {Oktyabrsky, Serge and Yakimov, Michael and Tokranov, Vadim and Murat, Pavel},
abstractNote = {Here, a picosecond-range timing of charged particles and photons is a long-standing challenge for many high-energy physics, biophysics, medical and security applications. We present a design, technological pathway and challenges, and some properties important for realization of an ultrafast high-efficient room-temperature semiconductor scintillator based on self-assembled InAs quantum dots (QD) embedded in a GaAs matrix. Low QD density (<; 1015 cm-3), fast (~5 ps) electron capture, luminescence peak redshifted by 0.2-0.3 eV from GaAs absorption edge with fast decay time (0.5-1 ns) along with the efficient energy transfer in the GaAs matrix (4.2 eV/pair) allows for fabrication of a semiconductor scintillator with the unsurpassed performance parameters. The major technological challenge is fabrication of a large volume (> 1 cm3 ) of epitaxial QD medium. This requires multiple film separation and bonding, likely using separate epitaxial films as waveguides for improved light coupling. Compared to traditional inorganic scintillators, the semiconductor-QD based scintillators could have about 5x higher light yield and 20x faster decay time, opening a way to gamma detectors with the energy resolution better than 1% and sustaining counting rates MHz. Picosecond-scale timing requires segmented low-capacitance photodiodes integrated with the scintillator. For photons, the proposed detector inherently provides the depth-of-interaction information.},
doi = {10.1109/TNS.2015.2502426},
journal = {IEEE Transactions on Nuclear Science},
number = 2,
volume = 63,
place = {United States},
year = {Wed Mar 30 00:00:00 EDT 2016},
month = {Wed Mar 30 00:00:00 EDT 2016}
}

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