TY - JOUR
T1 - Near-resonant two-photon absorption in luminescent CdTe quantum dots
AU - Khatei, Jayakrishna
AU - Suchand Sandeep, C. S.
AU - Philip, Reji
AU - Koteswara Rao, K. S.R.
PY - 2012/2/20
Y1 - 2012/2/20
N2 - We report the nonlinear optical absorption studies in two differently sized water-soluble cadmium telluride quantum dot (QD) samples, exhibiting first excitonic absorption peaks at 493 nm and 551 nm, respectively. An optical limiting behavior is observed for near-resonant excitation at 532 nm using nanosecond laser pulses, originating from the effective two-photon absorption (TPA) mechanism. The effective TPA coefficient ( eff) is measured to be in the range of 10 -12 m/W. This is one order of magnitude higher than the TPA coefficient () reported for off-resonant excitation. At this excitation wavelength, the smaller QD shows a relatively weaker photoluminescence and stronger nonlinear absorption.
AB - We report the nonlinear optical absorption studies in two differently sized water-soluble cadmium telluride quantum dot (QD) samples, exhibiting first excitonic absorption peaks at 493 nm and 551 nm, respectively. An optical limiting behavior is observed for near-resonant excitation at 532 nm using nanosecond laser pulses, originating from the effective two-photon absorption (TPA) mechanism. The effective TPA coefficient ( eff) is measured to be in the range of 10 -12 m/W. This is one order of magnitude higher than the TPA coefficient () reported for off-resonant excitation. At this excitation wavelength, the smaller QD shows a relatively weaker photoluminescence and stronger nonlinear absorption.
UR - https://www.scopus.com/pages/publications/84857774677
UR - https://www.scopus.com/pages/publications/84857774677#tab=citedBy
U2 - 10.1063/1.3687695
DO - 10.1063/1.3687695
M3 - Article
AN - SCOPUS:84857774677
SN - 0003-6951
VL - 100
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 8
M1 - 081901
ER -