An oscillator in which crosstalk can be reduced is provided. An oscillator includes a SQUID, a transmission line connected to the SQUID, a ground plane, and a first connection circuit disposed in a vicinity of a node of an electric field of a standing wave that is generated when the oscillator is oscillating, the first connection circuit connecting parts of the ground plane located on both sides of the transmission line to each other.

Ferrimagnetic oscillator magnetometers do not use lasers to stimulate fluorescence emission from defect centers in solid-state hosts (e.g., nitrogen vacancies in diamonds). Instead, in a ferrimagnetic oscillator magnetometer, the applied magnetic field shifts the resonance of entangled electronic spins in a ferrimagnetic crystal. These spins are entangled and can have an ensemble resonance linewidth of approximately 370 kHz to 10 MHz. The resonance shift produces microwave sidebands with amplitudes proportional to the magnetic field strength at frequencies proportional to the magnetic field oscillation frequency. These sidebands can be coherently averaged, digitized, and coherently processed, yielding magnetic field measurements with sensitivities possibly approaching the spin projection limit of 1 attotesla/√{square root over (Hz)}. The encoding of magnetic signals in frequency rather than amplitude relaxes or removes otherwise stringent requires on the digitizer.

A superconducting readout system employing a microwave transmission line, and a microwave superconducting resonator communicatively coupled to the microwave transmission line, and including a superconducting quantum interference device (SQUID), may be advantageously calibrated at least in part by measuring a resonant frequency of the microwave superconducting resonator in response to a flux bias applied to the SQUID, measuring a sensitivity of the resonant frequency in response to the flux bias, and selecting an operating frequency and a sensitivity of the microwave superconducting resonator based at least in part on a variation of the resonant frequency as a function of the flux bias. The flux bias may be applied to the SQUID by an interface inductively coupled to the SQUID. Calibration of the superconducting readout system may also include determining at least one of a propagation delay, a microwave transmission line delay, and a microwave transmission line phase offset.

A spin torque oscillator includes a first electrode, a second electrode and a device layer stack located between the first electrode and the second electrode. The device layer stack includes a spin polarization layer including a first ferromagnetic material, an assist layer including a third ferromagnetic material, a ferromagnetic oscillation layer including a second ferromagnetic material located between the spin polarization layer and the assist layer, a nonmagnetic spacer layer located between the spin polarization layer and the ferromagnetic oscillation, and a nonmagnetic coupling layer located between the ferromagnetic oscillation layer and the assist layer. The assist layer is antiferromagnetically coupled to the ferromagnetic oscillation layer through the non-magnetic coupling layer, and the assist layer has a magnetization that is coupled to a magnetization of the ferromagnetic oscillation layer.

Disclosed herein are methods and apparatuses for sequencing nucleic acids using a detection device, the detection device comprising a plurality of spin torque oscillators (STOs) and at least one fluidic channel. In some embodiments of a method, a nucleotide precursor is labeled with a magnetic nanoparticle (MNP), and the labeled nucleotide precursor is added to the fluidic channel of the detection device. It is determined whether at least one of the plurality of STOs is generating a signal. Based at least in part on the determination of whether the at least one of the plurality of STOs is generating the signal, it is determined whether the labeled nucleotide precursor has been detected.

Ferrimagnetic oscillator magnetometers do not use lasers to stimulate fluorescence emission from defect centers in solid-state hosts (e.g., nitrogen vacancies in diamonds). Instead, in a ferrimagnetic oscillator magnetometer, the applied magnetic field shifts the resonance of entangled electronic spins in a ferrimagnetic crystal. These spins are entangled and can have an ensemble resonance linewidth of approximately 370 kHz to 10 MHz. The resonance shift produces microwave sidebands with amplitudes proportional to the magnetic field strength at frequencies proportional to the magnetic field oscillation frequency. These sidebands can be coherently averaged, digitized, and coherently processed, yielding magnetic field measurements with sensitivities possibly approaching the spin projection limit of 1 attotesla/√{square root over (Hz)}. The encoding of magnetic signals in frequency rather than amplitude relaxes or removes otherwise stringent requires on the digitizer.

A magnetic device for magnetic random access memory (MRAM), spin torque MRAM, or spin torque oscillator technology is disclosed wherein a magnetic tunnel junction (MTJ) with a sidewall is formed between a bottom electrode and a top electrode. A passivation layer that is a single layer or multilayer comprising one of B, C, or Ge, or an alloy thereof wherein the B, C, and Ge content, respectively, is at least 10 atomic % is formed on the MTJ sidewall to protect the MTJ from reactive species during subsequent processing including deposition of a dielectric layer that electrically isolates the MTJ from adjacent MTJs, and during annealing steps around 400° C. in CMOS fabrication. The single layer is about 3 to 10 Angstroms thick and may be an oxide or nitride of B, C, or Ge. The passivation layer is preferably amorphous to prevent diffusion of reactive oxygen or nitrogen species.

According to various embodiments, a spin diode device may include a magnetic tunnel junction stack. The magnetic tunnel junction stack may include a lower magnetic layer, a tunnel barrier layer over the lower magnetic layer, and an upper magnetic layer over the tunnel barrier layer. The lower magnetic layer may include a lower magnetic film. The tunnel barrier layer comprising an insulating material. The upper magnetic layer may include an upper magnetic film. Each of the lower magnetic film and the upper magnetic film may have perpendicular magnetic anisotropy.

A magnetic device for magnetic random access memory (MRAM), spin torque MRAM, or spin torque oscillator technology is disclosed wherein a magnetic tunnel junction (MTJ) with a sidewall is formed between a bottom electrode and a top electrode. A passivation layer that is a single layer or multilayer comprising one of B, C, or Ge, or an alloy thereof wherein the B, C, and Ge content, respectively, is at least 10 atomic % is formed on the MTJ sidewall to protect the MTJ from reactive species during subsequent processing including deposition of a dielectric layer that electrically isolates the MTJ from adjacent MTJs, and during annealing steps around 400° C. in CMOS fabrication. The single layer is about 3 to 10 Angstroms thick and may be an oxide or nitride of B, C, or Ge. The passivation layer is preferably amorphous to prevent diffusion of reactive oxygen or nitrogen species.

An oscillator comprising, a cavity wherein the cavity comprises an electrical conductor. The oscillator comprising an electrical insulator disposed on a surface of the cavity; and a heterostructure disposed on a surface of the electrical insulator and having a first end and a second end, the heterostructure comprising one or more spin current source layers and one or more magnetic material layers. In response to an electrical current passed through the spin current source, an oscillation occurs in a plurality of magnetic domains of the magnetic material, wherein the oscillations have substantially the same phase.