TY - JOUR
T1 - Radiatively Dominated Charge Carrier Recombination in Black Phosphorus
AU - Bhaskar, Prashant
AU - Achtstein, Alexander W.
AU - Vermeulen, Martien J W
AU - Siebbeles, Laurens D A
PY - 2016/6/30
Y1 - 2016/6/30
N2 - We show that black phosphorus is a highly efficient infrared emitter. To study the carrier dynamics, excess electron-hole pairs were generated in bulk black phosphorus by irradiation with 3 MeV electron pulses. The transient microwave conductivity due to excess charges was measured as a function of time for different initial charge densities at temperatures in the range 203-373 K. A new global analysis scheme, including the treatment of intrinsic carriers, is provided, which shows that the recombination dynamics in black phosphorus, a low bandgap semiconductor, is strongly influenced by the presence of intrinsic carriers. The temperature dependence of the charge mobility and charge carrier decay via second-order radiative recombination is obtained from modeling of the experimental data. The combined electron and hole mobility was found to increase with temperature up to 250 K and decrease above that. Auger recombination is negligible for the studied densities of excess electron-hole pairs up to 2.5 × 1017 cm-3. For this density the major fraction of the excess electrons and holes undergoes radiative recombination. It is further inferred that for excess charge densities of the order of 1018 cm-3 electrons and holes recombine with near unity radiative yield. The latter offers promising prospects for use of black phosphorus as efficient mid infrared emitter in devices.
AB - We show that black phosphorus is a highly efficient infrared emitter. To study the carrier dynamics, excess electron-hole pairs were generated in bulk black phosphorus by irradiation with 3 MeV electron pulses. The transient microwave conductivity due to excess charges was measured as a function of time for different initial charge densities at temperatures in the range 203-373 K. A new global analysis scheme, including the treatment of intrinsic carriers, is provided, which shows that the recombination dynamics in black phosphorus, a low bandgap semiconductor, is strongly influenced by the presence of intrinsic carriers. The temperature dependence of the charge mobility and charge carrier decay via second-order radiative recombination is obtained from modeling of the experimental data. The combined electron and hole mobility was found to increase with temperature up to 250 K and decrease above that. Auger recombination is negligible for the studied densities of excess electron-hole pairs up to 2.5 × 1017 cm-3. For this density the major fraction of the excess electrons and holes undergoes radiative recombination. It is further inferred that for excess charge densities of the order of 1018 cm-3 electrons and holes recombine with near unity radiative yield. The latter offers promising prospects for use of black phosphorus as efficient mid infrared emitter in devices.
UR - http://www.scopus.com/inward/record.url?scp=84976878185&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.6b04741
DO - 10.1021/acs.jpcc.6b04741
M3 - Article
SN - 1932-7447
VL - 120
SP - 13836
EP - 13842
JO - The Journal of Physical Chemistry C
JF - The Journal of Physical Chemistry C
IS - 25
ER -