photodiode amplifier with notch/highpass filter?

Hi,
I'm trying to do an experiment which involves detecting a small
(~10^-6) modulation of a laser beam, at a frequency of about 60KHz.
The beam is about 1mW, and is itself chopped at about 35KHz.
I am currently using an unamplified photodiode and a lockin amplifier
to try to detect this signal,
but when I increase the sensitivity on the lockin to the level
necessary to detect the signal, the strong modulation at 35KHz causes
the amplifier to overload.

I am wondering if it is possible to build an amplifier for the
photodiode which can provide high transimpedance gain at 60KHz, but
which will not amplify the unwanted signal at 35KHz?
I have looked online, but have been unable to find examples of such a
circuit.

If you know how this can be accomplished or have any other
suggestions, your help would be greatly appreciated.

thanks,
Matthew

.

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