Single Atom Delivery into a Bottle Beam Trap Using an Optical Conveyor Belt and Quantum Coherent Gain in a Matterwave Transistor

Steven Burrows — Sat, 11 May 2019 17:58:38 +0000

Single Atom Delivery into a Bottle Beam Trap Using an Optical Conveyor Belt and Quantum Coherent Gain in a Matterwave Transistor Steven Burrows Sat, 05/11/2019 - 11:58

The work of this dissertation falls into two broad categories. In the first part, I describe
loading a single atom from a reservoir into a blue-detuned crossed vortex bottle beam trap using a
dynamic 1D optical lattice. The lattice beams are frequency chirped using acousto-optic modulators, which causes the lattice to move along its axial direction and behave like an optical conveyor
belt. A stationary lattice is initially loaded with approximately 6000 atoms from a reservoir, and
the conveyor belt transports them 1.1 mm from the reservoir to a bottle beam trap, where a single
atom is loaded via light-assisted collisions. Photon counting data confirm that an atom can be
delivered and loaded into the bottle beam trap 13.1 % of the time.

In part II, I describe a theory and experiment in the field of atomtronics that displays a
coherent gain mechanism for a triple-well matterwave transistor oscillator. I start with a wellestablished semi-classical description of an atomtronic transistor but model the system using a
many-body formalism. The quantum model predicts interesting physics when the atoms flowing
through the transistor have sufficiently low enough temperatures such that the motional state of a
dipole oscillating BEC, placed in the transistor itself, couples atom transitions between high lying
transistor energy eigenstates. In this regime, the coupling gives rise to a new gain mechanism
that increases the flux of matterwaves flowing out of the transistor system, compared to when the
coupling is absent. Our experiments suggest that the gain mechanism is coherent and increases the
spread of matterwave energy that flows out of the transistor.

B.. Dinardo, Single Atom Delivery into a Bottle Beam Trap Using an Optical Conveyor Belt and Quantum Coherent Gain in a Matterwave Transistor, University of Colorado Boulder, 2019.

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Shaken Lattice Interferometry

Steven Burrows — Mon, 21 May 2018 18:04:08 +0000

Shaken Lattice Interferometry Steven Burrows Mon, 05/21/2018 - 12:04

Shaken Lattice Interferometry

Since the first demonstrations in 1991, atom interferometry has been a burgeoning eld of
research. The work done in this eld is motivated by the potential sensitivity improvements that
atom-based devices can have over the current state-of-the-art light- and MEMS-based devices. This
dissertation presents a new and unique approach to atom interferometry in that we perform the
basic interferometric sequence of splitting, propagation, reflection, reverse-propagation, and recombination with atoms trapped in a phase-modulated (shaken) optical lattice. In both simulation
and experiment we demonstrate a one-dimensional shaken lattice interferometer configured as an
accelerometer. The interferometry sequence is developed through the use of learning and optimal
control algorithms that allow us to implement the desired state-to-state transformations and perform
the desired operations, e.g. splitting and recombination of the atoms trapped in the lattice.
This device has a sensitivity that scales as the square of the interrogation time and an ability to
distinguish both the magnitude and sign of an applied acceleration signal. Furthermore we show
that we can tailor the transfer function of the interferometer to be sensitive to a signal of interest,
e.g. an AC signal of a given frequency. Finally, we explore the analytics of shaken lattice
interferometry and oer some suggestions as to the future of this new technology.

C.A. Weidner, Shaken Lattice Interferometry, University of Colorado Boulder, 2018.

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Anderson Theses

Single Atom Delivery into a Bottle Beam Trap Using an Optical Conveyor Belt and Quantum Coherent Gain in a Matterwave Transistor

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Shaken Lattice Interferometry

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