Three-dimensional surface codes: Transversal gates and fault-tolerant architectures

One of the leading quantum computing architectures is based on the two-dimensional (2D) surface code. This code has many advantageous properties such as a high error threshold and a planar layout of physical qubits where each physical qubit need only interact with its nearest neighbours. However, the transversal logical gates available in 2D surface codes are limited. This means that an additional (resource intensive) procedure known as magic state distillation is required to do universal quantum computing with 2D surface codes. Here, we examine three-dimensional (3D) surface codes in the context of quantum computation. We introduce a picture for visualizing 3D surface codes which is useful for analysing stacks of three 3D surface codes. We use this picture to prove that the $CZ$ and $CCZ$ gates are transversal in 3D surface codes. We also generalize the techniques of 2D surface code lattice surgery to 3D surface codes. We combine these results and propose two quantum computing architectures based on 3D surface codes. Magic state distillation is not required in either of our architectures. Finally, we show that a stack of three 3D surface codes can be transformed into a single 3D color code (another type of quantum error-correcting code) using code concatenation.Comment: 23 pages, 24 figures, v2: published versio

Producing place atmospheres digitally: Architecture, digital visualisations practices and the experience economy

Computer generated images have become the common means for architects and developers to visualise and market future urban developments. This article examines within the context of the experience economy how these digital images aim to evoke and manipulate specific place atmospheres to emphasize the experiential qualities of new buildings and urban environments. In particular, we argue that CGIs are far from ‘just’ glossy representations but are a new form of visualising the urban that captures and markets particular embodied sensations. Drawing on a two year qualitative study of architects’ practices that worked on the Msheireb project, a large scale redevelopment project in Doha (Qatar), we examine how digital visualisation technology enables the virtual engineering of sensory experiences using a wide range of graphic effects. We show how these CGIs are laboriously materialised in order to depict and present specific sensory, embodied regimes and affective experiences to appeal to clients and consumers. Such development has two key implications. Firstly, we demonstrate the importance of digital technologies in framing the ‘expressive infrastructure’ (Thrift 2012) of the experience economy. Secondly, we argue that although the Msheireb CGIs open up a field of negotiation between producers and the Qatari client, and work quite hard at being culturally specific, they ultimately draw “on a Westnocentric literary and sensory palette” (Tolia-Kelly 2006) that highlights the continuing influence of colonial sensibilities in supposedly postcolonial urban processes.This research was funded by the ESRC (RES-062-23-0223)

Wireless aquatic navigator for detection and analysis (WANDA)

The cost of monitoring and detecting pollutants in natural waters is of major concern. Current and forthcoming bodies of legislation will continue to drive demand for spatial and selective monitoring of our environment, as the focus increasingly moves towards effective enforcement of legislation through detection of events, and unambiguous identification of perpetrators. However, these monitoring demands are not being met due to the infrastructure and maintenance costs of conventional sensing models. Advanced autonomous platforms capable of performing complex analytical measurements at remote locations still require individual power, wireless communication, processor and electronic transducer units, along with regular maintenance visits. Hence the cost base for these systems is prohibitively high, and the spatial density and frequency of measurements are insufficient to meet requirements. In this paper we present a more cost effective approach for water quality monitoring using a low cost mobile sensing/communications platform together with very low cost stand-alone ‘satellite’ indicator stations that have an integrated colorimetric sensing material. The mobile platform is equipped with a wireless video camera that is used to interrogate each station to harvest information about the water quality. In simulation experiments, the first cycle of measurements is carried out to identify a ‘normal’ condition followed by a second cycle during which the platform successfully detected and communicated the presence of a chemical contaminant that had been localised at one of the satellite stations

Invasion of the body snatchers: architecture and virtual space

Architecture, in one sense, has become part of the media: it has an aspect which is symbolic and semiotic, which is as ‘real’ in photography, film, television, advertising, computer games and literature as it is in our experience of landscapes, buildings and machines. But, I shall argue that the media, in one sense, have also become part of architecture, they have an aspect which we perceive as continuous with Cartesian space, and through this pseudo-physical presence they help shape and programme the space of habitation

Include 2011 : The role of inclusive design in making social innovation happen.

Include is the biennial conference held at the RCA and hosted by the Helen Hamlyn Centre for Design. The event is directed by Jo-Anne Bichard and attracts an international delegation