Quantum Computing: how to Estimate Error Probability in Logic Synthesis.

Date of Submission

December 2013

Date of Award

Winter 12-12-2014

Institute Name (Publisher)

Indian Statistical Institute

Document Type

Master's Dissertation

Degree Name

Master of Technology

Subject Name

Computer Science


Advance Computing and Microelectronics Unit (ACMU-Kolkata)


Sur-Kolay, Susmita (ACMU-Kolkata; ISI)

Abstract (Summary of the Work)

The interest in quantum computing began because it showed the potential to solve many classically intractable problems, as was evident from Shor’s discovery of an algorithm to factor large numbers in polynomial time and Grover’s algorithm to find a single object in an unassorted database. The main strength of quantum computers lay in the phenomenon of superposition, which gives it enormous information storing capability as compared to classical computers. But this does not come free of cost.Real quantum systems are open systems which can couple in an unwanted manner to an environment or control system and lose their intrinsic quantum nature through the process of decoherence, quantum noise, and imprecise measurement, preparation and control. Fortunately, it was discovered that under reasonable physical assumptions, that is, if the worst error probability of any component is below a certain threshold, a fault-tolerant quantum computation can be built.Ideally, an error-correcting circuit must be placed after every encoded component for error detection and recovery. But this entails a huge amount of physical resources, that is, additional gates and ancilla qubits. So we trace the error propagation in quantum circuits and place the error-correction sub-circuit only when the probability of errors exceed a certain cut-off.For encoding we have considered three quantum error correcting codes, namely BaconShor, Steane and Knill code. To calculate the error probability for different encoded gates at various levels of concatenation, we have analysed and designed an error analysis model for the physically realizable tile architecture that uses SWAP gates for movement of qubits locally. We have also designed a model for error propagation in quantum circuits and have tested it on benchmark circuits.


ProQuest Collection ID: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqm&rft_dat=xri:pqdiss:28843166

Control Number


Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.



This document is currently not available here.