Barton Zwiebach - Mastering Quantum Mechanics: Essentials, Theory, and Applications

Essentials, Theory, and Applications

Barton Zwiebach

The MIT Press
Cambridge, Massachusetts
London, England

2022 Barton Zwiebach

All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher.

The MIT Press would like to thank the anonymous peer reviewers who provided comments on drafts of this book. The generous work of academic experts is essential for establishing the authority and quality of our publications. We acknowledge with gratitude the contributions of these otherwise uncredited readers.

Library of Congress Cataloging-in-Publication Data.

Names: Zwiebach, Barton, 1954 author.

Title: Mastering quantum mechanics: essentials, theory, and applications / Barton Zwiebach,

Massachusetts Institute of Technology, Cambridge, MA.

Description: Cambridge, MA: The MIT Press, [2022] | Includes bibliographical references and index.

Identifiers: LCCN 2021016609 | ISBN 9780262046138 (hardcover)

Subjects: LCSH: Quantum theory.

Classification: LCC QC174.12.Z85 2022 | DDC 530.12dc23

LC record available at https:// lccn .loc .gov /2021016609

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To my wife, Gaby, with love

List of Figures

Left: The representation of the complex number z= a+ ibin the complex plane. Right: The unit-norm complex number ei has real part cos and imaginary part sin .

Left: A polarizer that transmits light linearly polarized along the direction. Right: Light linearly polarized at an angle relative to the xaxis, hitting the polarizer. The large double-sided arrow denotes the preferential direction of the polarizer, in this case along the xdirection.

Npolarizers whose preferential directions are tilted relative to each other.

An incident beam hitting a beam splitter results in a reflected beam and a transmitted beam. Left: incident beam coming from the top. Right: incident beam coming from the bottom.

A Mach-Zehnder interferometer consists of two beam splitters BS1 and BS2, two mirrors M1 and M2, and two detectors D0 and D1. An incident beam will be split into two beams by BS1. One beam, beam a, goes through the upper branch, which contains M1. The other beam, beam b, goes through the lower branch, which contains M2. The beams on the two branches recombine at BS2 and are then sent into the detectors. The configuration is prepared to produce an interference so that all incident photons end at the detector D0, with none at D1.

An elliptically polarized plane wave is specified by the parameters and a/b.