Quantum Computing on the Cover of Time Magazine

Quantum computing is featured on the cover of this week’s Time Magazine, the February 17th issue.  The story is of particular interest in our department, since Aaron Reinhard and his student coworkers are building an atomic physics experiment that aims to understand the interactions among ultracold, highly excited atoms.  These interactions could someday be used to build a scalable quantum computer.

The article in Time focuses on the D-Wave Two, a controversial new commercial product which claims to implement an adiabatic quantum computer which consists of 512 “qubits,” or quantum bits.  A quantum computer is a device where the individual bits, or the “ones” and ”zeros“ which encode all the information in the computer, are stored in quantum systems.  In a classical computer, each bit can be in either the “zero” state or the “one” state.  In a quantum computer, owing to the strange properties of quantum mechanics, each bit can be either in the zero state, the one state, or zero and one at the same time.  There are several very clever computing algorithms that harness this strange behavior to perform massively parallel operations.

An example of such an process, called Shor’s algorithm, involves the factorization of a large number into its prime factors.  Factorization is at the heart of nearly all protocols for data encryption and secure communication.  The increase in the speed at which a quantum computer would be able to factor a number compared to a classical computer scales exponentially with the number of bits.  This means that numbers which might take years to factor on the best modern classical computers might take seconds to factor using a quantum computer.  Numbers that would take the age of the universe to factor on a classical computer, could be factored in months.

The reason the $10 million D-Wave Two is controversial is that it purports to implement adiabatic quantum computation, or a very special kind of quantum computation.  Adiabatic quantum computers can only be used for optimization problems, or problems related to finding the fastest or most efficient way to do something.  They cannot be used to factor numbers.  Gate-type quantum computers are necessary for this task.  Adding to the controversy is the fact that several independent tests of the D-Wave Two have not shown any improvement in speed over a classical computer1,2.

Dr. Reinhard’s group is building an experiment where they will trap rubidium atoms and cool them to a few millionths of a degree above absolute zero.  They will then excite the atoms’ valence electrons to very high internal states (principal quantum numbers of 40-100) and study the interactions among these neutral atoms.  The goal is to understand the properties of the interactions so that they might someday be used to build a gate-based quantum computer made of neutral atoms.   The fundamental science involved in the interactions among neutral atoms is of significant interest, but the potential application to the important problem of quantum information is very exciting.

 

References:

1  Boixo et. al. (April 2013). Quantum annealing with more than one hundred qubits

2 Ronnow et. al. (January 2014). Defining and detecting quantum speedup

Systems Engineering Program Announced

On February 6, Otterbein officially announced a new major in systems engineering, to launch in fall 2015.  Systems engineering represents a broad-based engineering education which focuses on the principles of mechanical, industrial, and electrical engineering as well as physics and math.  We have received very positive feedback on our curriculum from local industry partners such as Xigent Automation Systems, Worthington Industries, Mettler Toledo, and Emerson Network Power.  Therefore, we are confident that our future graduates will be in high demand.

Professors Dave Robertson and Aaron Reinhard of the Physics Department were leaders in the development of this curriculum, and Reinhard was appointed interim director of the program in January 2015.  A national search is underway to hire a full-time director, who will start this coming August.

The 3+2 Cooperative Engineering program run by the Physics Department will continue, allowing students the opportunity to pursue areas of engineering other than systems.

For more information, see the Otterbein press release:

http://www.otterbein.edu/Spotlights/otterbein-announces-engineering-major-beginning-fall-2015

or the Systems Engineering  website:

http://www.otterbein.edu/public/Academics/Departments/Interdisciplinary/systems-engineering.aspx

or contact either Prof. Reinhard or Prof. Robertson.

MicroBooNE – Neutrino physics with liquid argon

The neutrino group at Otterbein (that is, myself and one or two students) are busy working on a new experiment called MicroBooNE at the Fermi National Accelerator Lab. This experiment measures the rates of different kinds of neutrino interactions with nuclei by looking at the ionized particle tracks left in a huge tank of liquid argon. An electric field “drifts” the ionization electrons to a set of wires for easy readout.

The wire cage that surrounds the detection volume is about 3m x 3m x 10m. This gets put into a huge tank (the cryostat) which holds 170 tons of liquid argon.

I’m busy working on several parts of this experiment: namely the event viewer. You can see some simulated data with my Argo Event Viewer. I’m also working on the DAQ (Data AQuisition) group, providing them tools for doing online monitoring of the data. This will allow us to keep an eye on the health of the detector as we set it up and run it.

A simulated electron neutrino as will be seen by the MicroBooNE liquid argon time projection chamber.
A simulated electron neutrino as will be seen by the MicroBooNE liquid argon time projection chamber.

Philip Kellogg will be working with me next summer trying to identify Michel electrons (electrons resulting from the beta-decay of stopped cosmic-ray muons) and using them to try to measure the energy response of the detector. With a little luck, this will make a great senior thesis. I’ll also be looking for one other lucky student to work on this project.

MicroBooNE is being built now; first data will probably start coming out around the time we start classes after the summer of 2014… but we get to have fun putting the whole thing together very soon.

You can ‘like’ MicroBooNE on their facebook page!

— Nathaniel

Cardinal Science Scholars Grant Renewed

The departments of Physics, Chemistry, and Mathematics have been awarded a grant of $629,000 by the National Science Foundation for the continuation and expansion of the Cardinal Science Scholars program (CSS).  The program was begun in 2009 and includes scholarship monies for talented students, as well as support for co-curricular activities designed to help students be successful in their academic and professional lives.  CS Scholars participate in mentoring groups, professional development activities, seminars, visits to local industries and laboratories, living-learning communities, and more.

Scholarships of $6k-10k per year are available to students in physics, engineering, chemistry, biochemistry and molecular biology, mathematics and computer science.  Please contact Prof. Joan Esson (Chemistry/BMB), Dave Robertson (Physics/Engineering), or Adriana Nenciu (Mathematics/Computer Science) if you have questions or would like more information.

Moving Forward with Engineering

The Otterbein Senate voted on November 20 to approve the creation of a new program in Systems Engineering.  This is an innovative, integrated engineering curriculum based on foundational courses in mechanical and electrical engineering, and advanced courses on industrial and complex systems analysis.  Profs. Dave Robertson and Aaron Reinhard of the Physics Department were leaders in this development, and Reinhard has assumed the position of Interim Director of Systems Engineering.  A national search is underway to hire a full-time Director, who will start this coming August.  The goal is to admit our first cohort of students in Fall 2015.

The 3+2 Cooperative Engineering program run by the Physics Department will continue, allowing students the opportunity to pursue areas of engineering other than systems.

Computer games in physics teaching

Students will know that I love computer games – we spend far too much time discussing them outside of class. But they can be useful even inside class. Here are a few I’d recommend for physics students or teachers:

A Slower Speed of Light is a simulation from MIT labs which shows all the effects one would see if you could move at a substantial fraction of the speed of light: the tunnel-vision effect, red- or blue-shifting, time dilation, etc.  Fun to play with for ten minutes.

Osmos is a sweet little game for the iPad, computer, or consoles, which gives you control of a bacterium-like creature that moves by expelling part of it’s mass as “exhaust”, and eats other objects in it’s 2-D universe.  Besides the original ideas of momentum conservation, later levels introduce some simple orbital mechanics, as large ‘stars’ and ‘planets’ effect the trajectory of all the little objects in your universe.  I’ve assigned this game as extra credit in my classical mechanics courses.

Kerbal Space Program is still in beta on Steam, but it’s clear from the brief tutorial that it’s both silly and serious at the same time – you can just build a monstrosity of a rocket and smash into the ground, or you can carefully perform rocket burns for orbital transfer and insertion to the “Mun”.  Might be a fun game to play in a small group, although the controls are not exactly intuitive.  A game to watch.

 

—Nathaniel

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