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تسجيل مستخدم جديدTowards coherent optical control of a single hole spin: Rabi rotation of a trion conditional on the spin state of the hole
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A hole spin is a potential solid-state q-bit, that may be more robust against nuclear spin induced dephasing than an electron spin. Here we propose and demonstrate the sequential preparation, control and detection of a single hole spin trapped on a self-assembled InGaAs/GaAs quantum dot. The dot is embedded in a photodiode structure under an applied electric-field. Fast, triggered, initialization of a hole spin is achieved by creating a spin-polarized electron-hole pair with a picosecond laser pulse, and in an applied electric-field, waiting for the electron to tunnel leaving a spin-polarized hole. Detection of the hole spin with picosecond time resolution is achieved a second picosecond laser pulse to probe the positive trion transition, where a trion is created conditional on the hole spin to be detected as a change in photocurrent. Finally, using this setup we observe a Rabi rotation of the hole-trion transition that is conditional on the hole spin, which for a pulse-area of $2pi$ can be used to impart a phase-shift of $pi$ between the hole spin states, a non-general manipulation of the hole spin.
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We demonstrate coherent optical control of a single hole spin confined to an InAs/GaAs quantum dot. A superposition of hole spin states is created by fast (10-100 ps) dissociation of a spin-polarized electron-hole pair. Full control of the hole-spin
is achieved by combining coherent rotations about two axes: Larmor precession of the hole-spin about an external Voigt geometry magnetic field, and rotation about the optical-axis due to the geometric phase shift induced by a picosecond laser pulse resonant with the hole-trion transition.
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