TAILIEUCHUNG - The Quantum Mechanics Solver 3

The Quantum Mechanics Solver 3 uniquely illustrates the application of quantum mechanical concepts to various fields of modern physics. It aims at encouraging the reader to apply quantum mechanics to research problems in fields such as molecular physics, condensed matter physics or laser physics. Advanced undergraduates and graduate students will find a rich and challenging source of material for further exploration. This book consists of a series of problems concerning present-day experimental or theoretical questions on quantum mechanics | 10 Summary of Quantum Mechanics Variational Method for the Ground State Consider an arbitrary state normalized to 1. The expectation value of the energy in this state is greater than or equal to the ground state energy E0 H E0. In order to find an upper bound to Eq one uses a set of trial wave functions which depend on a set of parameters and one looks for the minimum of E for these functions. This minimum always lies above Eq. 7 Identical Particles All particles in nature belong to one of the following classes Bosons which have integer spin. The state vector of N identical bosons is totally symmetric with respect to the exchange of any two of these particles. Fermions which have half-integer spin. The state vector of N identical fermions is totally antisymmetric with respect to the exchange of any two of these particles. Consider a basis nj i 1 2 . of the one particle Hilbert space. Consider a system of N identical particles which we number arbitrarily from 1 to N. a If the particles are bosons the state vector of the system with Ni particles in the state n1 N2 particles in the state n2 etc. is vN vN1 N2 1 np 1 2 np 2 . N np N where the summation is made on the N permutations of a set of N elements. b If the particles are fermions the state corresponding to one particle in the state n1 another in the state n2 etc. is given by the Slater determinant 1 ni 1 ni 2 ni 2 n2 1 nN 2 nN N ni N n2 . N nN Since the state vector is antisymmetric two fermions cannot be in the same quantum state Pauli s exclusion principle . The above states form a basis of the N fermion Hilbert space. 8 Time-Evolution of Systems 11 8 Time-Evolution of Systems Rabi Oscillation Consider a two-level system of Hamiltonian Ho hw0 . We couple these two states with a Hamiltonian Hi H We assume that the state of the system is at time t 0. The probability to find the system in the state at time t is w 1 sm CT 2 with ti w w0 w ii Time-Dependent Perturbation Theory We consider a system whose Hamiltonian

TỪ KHÓA LIÊN QUAN
TAILIEUCHUNG - Chia sẻ tài liệu không giới hạn
Địa chỉ : 444 Hoang Hoa Tham, Hanoi, Viet Nam
Website : tailieuchung.com
Email : tailieuchung20@gmail.com
Tailieuchung.com là thư viện tài liệu trực tuyến, nơi chia sẽ trao đổi hàng triệu tài liệu như luận văn đồ án, sách, giáo trình, đề thi.
Chúng tôi không chịu trách nhiệm liên quan đến các vấn đề bản quyền nội dung tài liệu được thành viên tự nguyện đăng tải lên, nếu phát hiện thấy tài liệu xấu hoặc tài liệu có bản quyền xin hãy email cho chúng tôi.
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.