RSS icon
Twitter icon
Facebook icon
Vimeo icon
YouTube icon

Beyond The Heisenberg Uncertainty Principle with Negative Mass Oscillators

November 30, 2015 - 11:00am
Speaker: 
Eugene Simon Polzik
Institution: 
University of Copenhagen, Denmark

Quantum oscillators ranging from a collective spin of an atomic
ensemble to a mechanical oscillator to an electrical oscillator are
central in many areas of physics. Generation of interesting quantum
states of such oscillators allows, for example, performing the most
precise measurements. We have recently demonstrated that a squeezed
state of a spin oscillator for which one quadrature has fluctuations
below the ground state level can be generated by a stroboscopic
quantum nondemolition measurement. However, sensing with the precision
beyond the vacuum state uncertainty in both position and momentum,
which appears to be prohibited by the uncertainty principle is
evenmore intriguing. We have demonstrated that this limitation can be
overcome by entangling an oscillator with a reference oscillator
characterized by an effective negative mass. The core idea is to
cancel the measurement back action of the joint measurement on the two
oscillators. Progress with the experimental demonstration of the back
action cancellation for a macroscopic mechanical oscillator and a
reference spin oscillator will be presented. In a more general sense,
this approach leads to trajectories without quantum uncertainties and
to achieving new fundamental bounds on the measurement precision.

CSS 2400
College Park, MD 20742

Subscribe to A Quantum Bit 

Quantum physics began with revolutionary discoveries in the early twentieth century and continues to be central in today’s physics research. Learn about quantum physics, bit by bit. From definitions to the latest research, this is your portal. Subscribe to receive regular emails from the quantum world. Previous Issues...

Sign Up Now

Sign up to receive A Quantum Bit in your email!

 Have an idea for A Quantum Bit? Submit your suggestions to jqi-comm@umd.edu