Quantum Information Research at NIST: Goals and Vision

What Good Is Quantum Information?

What is Quantum Information?

Quantum Computing

• Ion Qubits, Neutral Atom Qubits, and Superconducting Qubits
• Beam Me Up Einstein!
  NIST Demonstrates Teleportation
• Engineering Secrets: How to Entangle Ions

Quantum Communications

• Making a Quantum "Key"
• Quantum Information Theory

Selected NIST publications

Contact information

Beam Me Up Einstein! NIST Demonstrates Teleportation

Teleporation takes place between two locations inside an ion trap made of gold electrodes desposited onto alumina. The trap area is the horizontal opening near the center of the image. M.D. Barrett and J. Jost/NIST

NIST physicists were the first, along with a team in Austria, to “teleport” data from one atom to another. Teleportation could enhance the speed and efficiency of quantum computing by transferring data between distant qubits, or it could be a crucial step in detecting and correcting minor errors.

Unlike the “beaming” of people and objects between distant locations popularized in the Star Trek science fiction series, quantum teleportation describes the transfer of key properties of one atom to another atom without direct physical contact between them.

This may sound like magic. But teleportation merely exploits exotic features of quantum mechanics called superposition and entanglement (see “What is Quantum Information”).

Teleportation transfers the quantum properties of one atom to another atom. This includes the atom’s “spin” (which may be anywhere between spin up and spin down, representing 0 or 1 or both at the same time) and its “phase” (orientation to the left or right of a vertical plane). Scientists cannot simply measure and copy the spin and phase values, because single measurements reveal only a very small amount of information and destroy delicate quantum states.

Teleportation has been compared to faxing in that it reconstructs a quantum state indirectly. But, unlike faxing, it also destroys the original. The spin and phase values are teleported in two parts. The first part is transferred by entanglement; the other part is transferred by “corrections” using more conventional tools.

The NIST procedure teleports the quantum state of one beryllium ion to another ion. Three ions are required. First, two of the ions, say ions 1 and 3, are entangled and then placed in separate locations labeled A and B, respectively. Suppose ion 2 is also located at position A and is in a quantum state to be teleported to ion 3 in position B. Now ions 1 and 2 are manipulated so they become entangled, which indirectly shares information between ions 2 and 3. Then ions 1 and 2 are measured. The result will be one of four possible combinations of 0 and 1 (00, 01, 10, and 11). The result indicates the assumed state of ion 3, and which of four possible corrections need to be applied to ion 3 to complete the teleportation. The options are: (1) do nothing, (2) reverse the spin, (3) reverse the phase, or (4) reverse both spin and phase.

Date created: 4-11-06
Last updated: 4-18-06
Contact: inquiries@nist.gov