The rotation scheme of quantum states based on EPR pairs

In this paper, we give a further discussion of short-distance teleportation. We propose bidirectional, rotation and cyclic rotation teleportation schemes for short-distance participants, respectively. In our bidirectional transmission scheme, the quantum channel is still an EPR pair and an auxiliary qubit in the ground state [Formula: see text], and two participants can transmit an unknown single-qubit state to each other. In the rotation and cyclic rotation schemes, bidirectional transmission is performed between two adjacent participants in turn. The unknown state qubits of the participants collapse into the ground state after one bidirectional transmission, and can be used as auxiliary qubits in subsequent bidirectional transmission. After a complete state rotation, each participant has held the unknown state of the other participants, and the last one owned by the participant is still the original unknown state. Although the schemes we proposed are applicable to a small range of transmission, they have certain advantages in saving quantum resources.

Bubble NoC – A Low Energy Network-on-Chip with Small Footprint and High Performance

<div>The Bubble NoC is based on simplicity and provides outstanding performance. Flow control is implemented by <i>bubbles</i>, which are inserted between the flits. The logic resembles a traffic situation where a vehicle only moves if the next position is empty. When a flit moves, a bubble is created behind it, and when there is a blocking the bubbles are collapsed as the flits behind are packed together. Even when the Bubble NoC is saturated, it degrades gracefully, and the execution continues.</div><div> Deterministic prerouting is used, with the address stored as markers in a 2 out of 32 code. The routing algorithm shifts the address one step at each hop and turns or finishes when a marker starts the address.</div><div> The physical implementation is a mesh of <i>streets</i> containing duplex links of 38 wires carrying 32-bit payload. Signaling is based on current injection that charges the wires. A switch is placed in a four-way crossing, with a fifth local connection into a street. The switch contains input registers for each approaching street. Straight through traffic is simply passed on, and a diagonal gate is used for turning traffic.</div><div> All switches are bidirectional transmission gates, and the control is distributed as a sidewalk in a few µm of the periphery surrounding the intersection. In a 14 nm technology, the streets are 8 μm wide, the crossing is 17 μm in square, the hop frequency 6.67 GHz and the energy for a datapath 4.1 fJ/bit/hop (150 µm).</div>

Bubble NoC – A Low Energy Network-on-Chip with Small Footprint and High Performance

<div>The Bubble NoC is based on simplicity and provides outstanding performance. Flow control is implemented by <i>bubbles</i>, which are inserted between the flits. The logic resembles a traffic situation where a vehicle only moves if the next position is empty. When a flit moves, a bubble is created behind it, and when there is a blocking the bubbles are collapsed as the flits behind are packed together. Even when the Bubble NoC is saturated, it degrades gracefully, and the execution continues.</div><div> Deterministic prerouting is used, with the address stored as markers in a 2 out of 32 code. The routing algorithm shifts the address one step at each hop and turns or finishes when a marker starts the address.</div><div> The physical implementation is a mesh of <i>streets</i> containing duplex links of 38 wires carrying 32-bit payload. Signaling is based on current injection that charges the wires. A switch is placed in a four-way crossing, with a fifth local connection into a street. The switch contains input registers for each approaching street. Straight through traffic is simply passed on, and a diagonal gate is used for turning traffic.</div><div> All switches are bidirectional transmission gates, and the control is distributed as a sidewalk in a few µm of the periphery surrounding the intersection. In a 14 nm technology, the streets are 8 μm wide, the crossing is 17 μm in square, the hop frequency 6.67 GHz and the energy for a datapath 4.1 fJ/bit/hop (150 µm).</div>

10 Gb/s Bidirectional Transmission with an Optimized SOA and a SOA-EAM Based ONU

We investigated the application of a semiconductor optical amplifier (SOA) and an SOA electro-absorption modulator (SOA-EAM) as attractive, low-cost solutions in passive optical networks (PONs). The main characteristics of an SOA with optimal performance for phase and amplitude modulation were tested. Additionally, a 10 Gb/s bidirectional transmission with an optical network unit (ONU) transmitter integrated with a distributed feedback (DFB) laser, electro-absorption modulator (EAM), and SOA was designed. The upstream (US) and downstream (DS) receiver sensitivities at the forward error correction (FEC) level reached −29.5 dBm and −33.5 dBm for back-to-back (BtB) fiber and −28.9 dBm and −33.1 dBm for 20 km fiber. For multichannel transmission, the US receiver sensitivities reached −28.8 dBm and −28.2 dBm for BtB and 20 km fibers, and the DS receiver sensitivities reached −33 dBm and −32.6 dBm for BtB and 20 km fibers, respectively.