What is it about?
There are limits to how much energy can be absorbed within a given region of space, but these limits do not apply to absorbers that include a second source of energy. This paper demonstrates that a pulse of energy sent into a cavity can be completely withdrawn by sending a second pulse into the cavity. Although this may sound counter-intuitive, this result is shown theoretically and experimentally.
Why is it important?
Active absorption of pulses has been addressed using time-reversal techniques. Here, we have shown a different method that relies on the geometry of the cavity and shape (modulation) of the pulse, but is not time-reversal.
The following have contributed to this page: Dr Robert N Foster