Before I tell you about David, I should mention one of his specialties is Attosecond Science, which is the study of processes that occur on a time scale of a few "attoseconds "(1×10 to the power−18 of a second (one quintillionth of a second)) or less. Examples include the ionization and recollision of an electron from its parent atom or molecule.
So, David is also an expert in Quantum Information and Ion trapping technology. In 2002 proposed the Quantum CCD (quantum charged-couple device) architecture for scaling up the ion trap quantum computers to many-qubit processors.
Circa 2002 David. Kielpinsky et al. proposed a novel design, the quantum CCD (quantum charge-coupled device) architecture for scaling up ion trap quantum computers to many-qubit processors. This architecture, if constructed, can help scale up to 70, 100, 700, or 7000 trapped qubits that we can use for flipping, doing deep gates for more complex circuits, as long as the gate fidelity (error correction) and coherence time remain at %99.999999 or even more 9s. The architecture is represented schematically in this post. It is based on a surface trap design. The trapped Ions are shuttled to different processor sections using precision classical computer software. Shuttling is implemented by applying time-varying potentials to DC electrodes that line the trap axis. The trap made based on classical physics and not quantum ,and the ions are practically atomic clocks by nature in high precision (identical) and long coherence time. I will cover that part in another post. Back to his proposed plan; after trapping and shuttling, Information is stored in short ion chains, which can be split apart for individual-ion addressing and brought back together for entangling operations. The junctions, where the trap axis forks or bends around corners, interconnect the 2D array of trapping zones. There are many advantages to this architecture according to David:
Short ion chains are more robust than longer chains.
Long ion chains are stored in traps with lower axial trap frequency for a given radial frequency. These tend to have higher heating rates since lower energy quanta are required to promote the ions to higher energy emotional modes. Further, as the number of ions in a single trap increases, so does the density of motional modes of the ion chain, making it much more difficult to address specific motional modes to perform entangling gates.
Using the current standard photolithographic techniques, ion shuttling without significant heating has already been demonstrated- built with multi zones containing hundreds of traps.
Here is one of the companies that can build such ion trap.
We use conventional microfabrication techniques to fabricate single-layer surface-electrode ion traps . Initially, a dielectric substrate, typically Aluminium Nitride (AlN), is coated with a bilayer thin film composed of titanium and gold. The first acts as a good adhesion layer to hold the trap structures. The second one plays an important role as a starting conductive layer. Followed by a photolithography step, in which parts of a previously UV-exposed resist are exposed on the conductive layer, the substrate is placed in an electrolyte solution to grow gold electrodes by electroplating.
This method allows the possibility of building large (height-to-width) aspect ratio structures. As shown in the picture on the left side, trap features as thick as 15 µm and gaps of about 3 µm can be fabricated.
Here is another document from David: Laser Cooling of Trapped ions:
In this post, we review his proposal and look into some sample.
Kommentare