1. A method for producing a high frequency optical signal component representative of a high frequency electrical signal component, comprising the steps of:
providing a layered semiconductor structure including a semiconductor drain region comprising at least one drain layer, a semiconductor base region disposed on said drain region and including at least one base layer, and a semiconductor emitter region disposed on a portion of said base region and comprising an emitter mesa that includes at least one emitter layer;
providing, in said base region, at least one region exhibiting quantum size effects;
providing a basedrain electrode coupled with said base region and coupled with said drain region, and providing an emitter electrode coupled with said emitter region, said basedrain electrode having a first portion on an exposed surface of said base region and a further portion coupled with said drain region;
providing an aperture disposed over said emitter region;
applying signals with respect to said basedrain and emitter electrodes to produce light emission from said base region, said step of providing an aperture further comprising providing an optical cavity for said light emission in the region between said first portion of the basedrain electrode and said emitter electrode; and
scaling said aperture to control the speed of light emission response to said high frequency electrical signal component.
2. The method as defined by claim 1, wherein said emitter mesa has a substantially rectilinear surface portion, and wherein said step of providing said electrodes comprises providing said emitter electrode along one side of said surface portion of the emitter mesa and providing the first portion of said basedrain electrode on a portion of the base region surface adjacent the opposite side of said emitter mesa surface portion.
3. The method as defined by claim 1, wherein said step of providing said electrodes further comprises providing said emitter electrode and the first portion of said basedrain electrode as opposing linear conductive strips.
4. The method as defined by claim 1, wherein said cavity is substantially rectangular, and wherein said scaling of lateral dimensions comprises providing said cavity with linear dimensions of about 10 \u03bcm or less.
5. The method as defined by claim 1, wherein said cavity is substantially rectangular, and wherein said scaling of lateral dimensions comprises providing said cavity with linear dimensions of about 5 \u03bcm or less.
6. The method as defined by claim 1, wherein said high frequency electrical signal component has a frequency of at least about 2 GHz.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. In a system that receives an optical signal, a detector that attenuates the optical signal based on an optical power of the optical signal, the detector comprising:
a detecting layer that receives an incident optical signal and generates a current that is related to an optical power of the incident optical signal;
a PIN structure connected to the detecting layer such that the incident optical signal passes through the PIN structure before the detecting layer; and
a control module that monitors the optical power of the incident optical signal detected by the detecting layer, wherein the control module generates a bias voltage to reverse bias the PIN structure when the optical power exceeds a threshold such that the incident optical signal is attenuated by the PIN structure before being detected by the detecting layer.
2. A detector as defined in claim 1, wherein the detecting layer is a PIN diode or an APD diode.
3. A detector as defined in claim 1, wherein an I layer of the PIN structure has a thickness, wherein an attenuation of the incident optical signal is related to the thickness of the I layer.
4. A detector as defined in claim 1, wherein the detecting layer is formed on a first side of a substrate and the PIN structure is formed on a second side of the substrate.
5. A detector as defined in claim 1, wherein the PIN structure is formed on a substrate and the detecting layer is formed on the PIN structure.
6. A detector as defined in claim 1, wherein the control module controls the bias voltage such that the PIN structure is forward biased when the optical power is below the threshold.
7. A detector as defined in claim 1, wherein the control module varies a magnitude of the bias voltage according to the optical power such that the optical signal is variably attenuated.
8. A detector as defined in claim 1, further comprising a lens to focus the incident optical signal on the detecting layer.
9. A method for variably attenuating an optical signal, the method comprising:
receiving an optical signal with a detector such that the optical signal is focused on a detecting diode of the detector, wherein the optical signal passes through a PIN structure of the detector before being focused on the detecting diode;
monitoring an optical power of the optical signal;
applying a forward bias to the PIN structure when the optical power is below a threshold; and
applying a reverse bias to the PIN structure when the optical power exceeds the threshold such that the optical signal is partially absorbed.
10. A method as defined in claim 9, wherein reverse biasing the PIN structure when the optical power exceeds the threshold such that the optical signal is partially absorbed further comprises controlling a bias voltage that is applied to the PIN structure.
11. A method as defined in claim 10, wherein controlling the bias voltage that is applied to the PIN structure further comprises:
increasing the bias voltage as the optical power increases past the threshold such that the reverse bias increases to variably attenuate the incident optical signal;
decreasing the bias voltage as the optical power decreases toward the threshold; and
applying a forward bias to the PIN structure when the optical power drops below the threshold.
12. A method as defined in claim 9, wherein applying a reverse bias to the PIN structure when the optical power exceeds the threshold such that the optical signal is partially absorbed farther comprises adjusting the reverse bias such that the detector is not saturated by the incident optical signal.