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As a postscript: the dual-amplifier version of the circuit is not just a teaching aid. You can use it and it will work fine.

A FET may still be preferable because some can work at gigahertz frequencies, while unity-gain-stable op-amps usually end at low hundreds of MHz. But for megahertz-range signals, either approach will do.

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This is cool. Have you built it?

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Yes. One of the wackiest aspects of it is that you can actually place a 1 kΩ resistor across the photodiode's terminals, and the amplifier keeps working fine. Intuitively, it should break the circuit by providing a current bypass path. Yet, there's never any real current through the resistor because the voltages are essentially identical.

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