Optically measuring electric field intensities

1. A method for measuring an intensity of an electric field, comprising:

positioning an electro-optically responsive optical resonator in the electric field, the optical resonator having first and second optical reflectors and an optical cavity located between the reflectors, one of the optical reflectors being a distributed Bragg reflector;

transmitting light through the first optical reflector and into the optical resonator; and

receiving a portion of the light transmitted into the optical resonator, the portion being received through the first optical reflector.

2. The method of claim 1 , further comprising:

determining an intensity of an electric field in the optical resonator by measuring a quantity indicative of a phase retardation for the received light.

3. The method of claim 1 , wherein the first optical reflector has a substantially higher transmissivity than the second optical reflector.

4. The method of claim 3 , wherein the second reflector has a transmissivity that is at least 1.6 times the transmissivity of the first reflector.

5. The method of claim 2 , wherein the optical resonator includes a group III-V semiconductor with zinc-blende crystal structure.

6. The method of claim 1 , wherein the optical resonator has a thickness of less than about 5 microns.

7. The method of claim 3 , wherein both optical reflectors are distributed Bragg optical reflectors.

8. The method of claim 1 , wherein a substantial portion of the received light has made multiple reflections inside the optical resonator.