1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Infrared quantum counting by nondegenerate two photon conductivity in GaAs
Rent:
Rent this article for
USD
10.1063/1.3089380
/content/aip/journal/apl/94/8/10.1063/1.3089380
http://aip.metastore.ingenta.com/content/aip/journal/apl/94/8/10.1063/1.3089380
View: Figures

Figures

Image of FIG. 1.
FIG. 1.

(a) Infrared quantum counting by ND-TPA. A pump photon from a high intensity beam promotes a valence band electron to a virtual state in the semiconductor gap. A second photon (signal) completes the transition to a real conduction band state. The electron is then accelerated in the space charge region, emitted above the vacuum energy level and induces a photocurrent. (b) Experimental setup: two nearly collimated beams are combined using a BS. Parasitic high energy (short wavelength) photons are filtered out by a high pass filter. Beams are focused through an aspheric lens (Asph. L) on a GaAs photocathode. The pump beam area on the GaAs detector is chosen far larger than the signal one in order to (i) minimize nonlinear absorption effects due to the pump beam and to (ii) stabilize the overlap between the two beams against vibrations.

Image of FIG. 2.
FIG. 2.

(a) D pump TPA count rate as a function of the pump power (subtracted on the following graphs). (b) Measured D- and ND-TPA photocounts due to signal photons at various fixed pump powers as a function of the signal power: the black star (solid red line) represents experimental photocounts (extrapolated fitted) when no pump is used (i.e., D-TPA). The inset shows the amplification due to ND-TPA effect compared to the D-TPA signal alone.

Image of FIG. 3.
FIG. 3.

(a) ND-TPA photocounts as a function of the signal power for different pump intensities. The two solid lines represent a linear (slope 1) and a quadratic (slope 2) evolution profile. The inset displays the ratio at fixed pump and signal power for different signal wavelengths. (b) ND-TPA normalized efficiency for different pump and signal intensities.

Loading

Article metrics loading...

/content/aip/journal/apl/94/8/10.1063/1.3089380
2009-02-24
2014-04-19
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Infrared quantum counting by nondegenerate two photon conductivity in GaAs
http://aip.metastore.ingenta.com/content/aip/journal/apl/94/8/10.1063/1.3089380
10.1063/1.3089380
SEARCH_EXPAND_ITEM