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Coherent manipulation of semiconductor quantum bits with terahertz radiation
B E Cole1, J B Williams, B T King
1Institute for Quantum Engineering, Science and Technology, Department of Physics, University of California, Santa Barbara 93106, USA.
Nature
|March 10, 2001
Summary
Researchers demonstrate that electrons bound to donor impurities in semiconductors can act as quantum bits (qubits). These semiconductor qubits can be manipulated using terahertz radiation, paving the way for new quantum computing research.
Area of Science:
- Quantum Computing
- Semiconductor Physics
Background:
- Quantum bits (qubits) are essential for quantum information processors.
- Understanding manipulation and decoherence of semiconductor qubits is crucial.
- Current semiconductor qubits face challenges in manipulation and decoherence.
Purpose of the Study:
- To investigate semiconductor donor impurities as model qubits.
- To demonstrate coherent manipulation of electron states in semiconductors.
- To explore decoherence processes in semiconductor qubits.
Main Methods:
- Utilized intense terahertz radiation pulses.
- Induced coherent, damped Rabi oscillations.
- Focused on low-lying states of donor impurities in Gallium Arsenide (GaAs).
Main Results:
- Demonstrated coherent manipulation of quantum-confined extrinsic electrons in semiconductors.
- Showcased electron states behaving like atomic electrons within a semiconductor host.
- Observed Rabi oscillations indicating qubit control.
Conclusions:
- Hydrogen-atom-like electron states in semiconductors can serve as model qubits.
- Coherent manipulation of semiconductor qubits is achievable.
- This system offers a platform for studying decoherence and testing qubit manipulations.
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