Novel photonic filter and receiver based on whispering gallery mode microresonators

We describe two new devices based on whispering gallery mode microresonators. The first device, a multipole filter, is based on coupled microresonators, the frequency of which is trimmed in situ to produce the desired filter function. The second device is based on a lithium niobate microresonator, which can detect applied microwave signals with power as low as 2.5 nW.