Instrumentation for quantum computers

• Main Author: Huang, Wei-Han, 1979-
• Other Authors: Isaac L. Chuang.
• Format: Others
• Language: English
• Published: Massachusetts Institute of Technology 2006
• Subjects: Electrical Engineering and Computer Science.
• Online Access: http://hdl.handle.net/1721.1/30104

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2004. === Includes bibliographical references (p. 209-215). === Quantum computation poses challenging engineering and basic physics issues for the control of nanoscale systems. In particular, experimental realizations of up to seven-qubit NMR quantum computers have acutely illustrated how quantum circuits require extremely precise control instrumentation for pulsed excitation. In this thesis, we develop two general-purpose, low-cost pulse programmers and two Class E power amplifiers, designed for precise control of qubits and complex pulse excitation. The first-generation pulse programmer has timing resolutions of 235 ns, while the second-generation one has resolutions of 10 ns. The Class E power amplifier has [mu]s transient response times, a high quality-factor, and a small form factor. The verification of the pulse programmer and the Class E power amplifier is demonstrated using a customized nuclear quadrupole resonance (NQR) spectrom- eter, which incorporates both devices. The two devices control the generation of RF pulses used in NQR experiments on paradichlorobenzene (C₆H₄C₁₂) and sodium nitrite (NaNO₂). The NQR signals originating from ¹⁴N in sodium nitrite and from ³⁵Cl in paradichlorobenzene are measured using the NQR spectrometer. The pulse programmer and the Class E power amplifier represent first steps towards development of practical NMR quantum computers. === by Wei-Han Huang. === S.M.