Coherent ultrafast measurement of time-bin encoded photons.

Coherent generation of time-bin entangled photon pairs using the biexciton cascade and cavity-assisted piecewise adiabatic passage

We present a scheme to realize a deterministic solid-state source of time-bin entangled photon pairs using cavity-assisted piecewise adiabatic passage in a single quantum dot. The quantum dot is embedded inside a semiconductor microcavity, and the interaction of a coherent superposition of two temporally separated input pulses and the cavity mode leads to a piecewise adiabatic passage, which pr...

Ultrafast coherent control of angular momentum during a one-photon excitation

Ultrafast coherent excitation of a trapped ion qubit for fast gates and photon frequency qubits.

We demonstrate ultrafast coherent excitation of an atomic qubit stored in the hyperfine levels of a single trapped cadmium ion. Such ultrafast excitation is crucial for entangling networks of remotely located trapped ions through the interference of photon frequency qubits, and is also a key component for realizing ultrafast quantum gates between Coulomb-coupled ions.

Temporal heterodyne detector for multitemporal mode quantum state measurement

We propose a novel method for measuring the multitemporal mode quantum state of repetitive radiation fields with ultrafast temporal resolution. The technique incorporates spectrometers at the output ports of a DC-balanced four-port apparatus. The signal field to be measured is delayed in time with respect to an ultrashort local oscillator pulse which is taken to be in a large-amplitude single t...

Ultrafast Coherent Control of Spin Precession Motion by Terahertz Magnetic Pulses

We demonstrated coherent control of spin precession motion due to the ferromagnetic resonance induced by magnetic field component of ultrashort terahertz pulses. The amplitude of the precession can be controlled by the pulse separation time of the double pulse excitation technique. We succeeded in observing the energy transfer between spin and photon systems, and the energy of the spin system i...