Introduction to Nanomechanics (Spring 2012) Martino Poggio

Introduction to Nanomechanics L = 120  m w = 3  m t = 100 nm E Si = 169 GPa k = 73  m x rms = 9 Å for T = 4.2 K

Introduction to Nanomechanics3 120 µm k = 60  N/mf = 3 kHzQ = 50,000 at 4K 100 nm thick shaft 1 µm thick mass loading Fabricated by B. Chui - IBM Ultrasensitive Cantilevers

Introduction to Nanomechanics Frequency (Hz) E-3 1E-4 1E-5 Sprectral density (Å 2 /Hz)

Real-time detection of nuclear spin polarization time (s) Natural spin fluctuations Thermal cantilever noise s X = 0.30±0.08 Å 2 2 s Y = 0.056±0.008 Å 2 2  m = 3.5 s Cantilever amplitude (Angstrom) Experiment with N ~ 10 6 spins ( 19 F in Calcium fluoride) Introduction to Nanomechanics

Frequency (Hz) Spectral density (Å 2 /Hz) Cantilever thermal noise Statistically polarized spin signal from 19 F nuclei in calcium fluoride Power Spectral Density of Nuclear Spin Polarization Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics9 What causes dissipation?

Introduction to Nanomechanics10 What causes dissipation?

How to measure dissipation? Ring-down Drive Frequency Sweep Measuring thermal noise spectrum Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics

Introduction to Nanomechanics19 Improving cantilever dissipation

Introduction to Nanomechanics

Introduction to Nanomechanics