Electro-optic time lensing with an intense single-cycle terahertz pulse

We demonstrate that an intense single-cycle terahertz (THz) pulse can act as a time lens to phase modulate and compress a copropagating ultrashort laser pulse. By using the THz-induced phase modulation as a time lens and a glass plate as a group velocity dispersive element, we have compressed an unchirped {approx} 165 fs laser pulse to {approx} 45 fs.