HW8_sol - 11/20/06 ECE 495W, Fall’06 MSEE 13010,er 330P...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 11/20/06 ECE 495W, Fall’06 MSEE 13010,er 330P —— 420P Fundamentals of N anoelectronics All exercises, section numbers and page numbers refer to S.Datta, Quantum Transport: Atom to Transistor, Cambridge (2005) HW#8: Due Friday Dec.1 in class. Please turn in a copy of your MATLAB code for Problem 1. You can use the MAT LAB codes at the end of the text as a guide, but the codes you turn in should be your own work, not copied from the text. Please study the examples in Section 9.5, page 240. Problem 2: Consider an infinite wire modeled as a discrete lattice with points spaced by ‘ , a having a Hamiltonian with H n,” = 2t0 and H WM =— t0 = Hn,n_1 (all other elements are zero), such that the dispersion relation is given by E = 2t0 (1— cos ka). What is the local density of states at the point “0”, D(O,E) ? Problem 3: Suppose we cut the wire in Problem 2 into two separate semi-infinite wires as shown so that H01 = H10 = 0 (other elements of the H—matrix remain unchanged). cut What is the local density of states at the point “0”, D(O,E) ? £ 4‘ 2/1 74:0]; H ’ [we] ) 5.1 3 [#606 a] _ who *i g : [wa'fed J Problem 4: Consider the wire in Problem 3 channel source The transmission WE) for this wire is obviously zero since electrons cannot go from left to right. But suppose we Wish to get this result formally by evaluating the expression Trace [I‘IGI‘ZG+] 2: 0 We treat points “0” and “1” as the channel described by the Hamiltonian [H] = [O 0% J 0 and the rest as the source and drain contacts described through (2x2) self—energy matrices. (a) What are 21 and 22? (b) What are 1‘1 and F2? (c) What is [G]? (d) Show that Trace [I‘IGI‘ZG+] = 0. 21: *WW' 0 22"[0 0 mil ...
View Full Document

This note was uploaded on 02/19/2012 for the course ECE 495w taught by Professor Supriyodatta during the Fall '06 term at Purdue University-West Lafayette.

Page1 / 4

HW8_sol - 11/20/06 ECE 495W, Fall’06 MSEE 13010,er 330P...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online