Bypassing the bandwidth theorem with PT symmetry

摘要: The beat time ${\ensuremath{\tau}}_{\mathrm{fpt}}$ associated with the energy transfer between two coupled oscillators is dictated by bandwidth theorem which sets a lower bound ${\ensuremath{\tau}}_{\mathrm{fpt}}\ensuremath{\sim}1/\ensuremath{\delta}\ensuremath{\omega}$. We show, both experimentally and theoretically, that active LRC electrical parity-time ($\mathcal{PT}$) symmetry bypass imposed theorem, reducing to zero while retaining real valued spectrum fixed eigenfrequency difference $\ensuremath{\delta}\ensuremath{\omega}$. Our results foster design strategies lead (stable) pseudounitary wave evolution, may allow for ultrafast computation, telecommunication, signal processing.