Efficient Spatial Redistribution of Quantum Dot Spontaneous Emission from 2D Photonic Crystals

We investigate the modification of the spontaneous emission dynamics and external quantum efficiency for self-assembled InGaAs quantum dots coupled to extended and localised photonic states in GaAs 2D-photonic crystals. The 2D-photonic bandgap is shown to give rise to a 5-10 times enhancement of the external quantum efficiency whilst the spontaneous emission rate is simultaneously reduced by a comparable factor. Our findings are quantitatively explained by a modal redistribution of spontaneous emission due to the modified local density of photonic states. The results suggest that quantum dots embedded within 2D-photonic crystals are suitable for practical single photon sources with high external efficiency

Reviving Bank Antirust

After decades of disuse, antitrust is back. Renewing the United States’ longstanding distrust of concentrated economic power, antimonopoly scholars have documented widespread harms of corporate “bigness” and inspired policy initiatives to de-concentrate the U.S. economy. To date, however, the new antitrust movement has largely overlooked a key cause of commercial concentration: the rapid consolidation of the U.S. banking sector. More than thirty thousand banks served local communities a century ago, but today just six financial conglomerates control half of the U.S. banking system. Bank consolidation, in turn, has spurred conglomeration throughout the economy. As the Supreme Court recognized in 1963, “[C]oncentration in banking accelerates concentration generally.” This Article contends that scholars and policymakers have neglected bank antitrust law for the past forty years and thereby encouraged excessive consolidation in the banking sector and the broader economy. It argues that policymakers’ current approach to bank antitrust—premised on a narrow conception of consumer welfare—has failed in two critical respects. First, it has failed on its own terms, as bank mergers have increased the cost and reduced the availability of basic financial services. Second, because of its limited focus on consumer prices, the prevailing standard has ignored numerous nonprice harms stemming from bank consolidation, including diminished product quality, heightened entry barriers, and greater macroeconomic instability. To correct these shortcomings, this Article proposes a roadmap for reviving bank antitrust. It recommends strengthening the analytical tools used to identify anticompetitive bank mergers and rejecting a narrow focus on consumer prices in favor of a more comprehensive analysis of the costs that bank consolidation imposes on society. Reviving bank antitrust in this way is critical to enhancing competition in the financial sector and throughout the U.S. economy

Board to Death: How Busy Directors Could Cause the Next Financial Crisis

In the aftermath of the Great Recession, shareholders and regulators expect financial institution boards of directors to play an active role in risk management. To date, however, shareholders, policymakers, and academics have ignored a critical shortcoming: the directors of the United States’ largest financial institutions are too busy to fulfill their governance responsibilities. Many financial institution directors hold full-time executive positions, and most serve on the board of at least one other company. Although these outside commitments provide important learning and networking opportunities, they also contribute to cognitive overload and limit the time that directors spend assessing strategy and risk. This Article argues that overcommitted directors impair the governance of large financial institutions. These firms, by virtue of their complexity and systemic importance, require enhanced risk monitoring that busy directors are ill-equipped to provide. Nonetheless, the boards of many large financial institutions remain alarmingly overcommitted. Through a series of case studies—including Wells Fargo’s fraudulent accounts scandal and JPMorgan’s London Whale trades—this Article explores how busy directors inhibit oversight of management, increase the risk of firm failure, and could cause the next financial crisis. This Article proposes a series of reforms to alleviate director overcommitment and thereby enhance the stability of the financial system

Modernizing Bank Merger Review

Sixty years ago, Congress established a federal pre-approval regime for bank mergers to protect consumers from then-unprecedented consolidation in the banking sector. This process worked well for several decades, but it has since atrophied, producing numerous “too big to fail” banks. This Article contends that regulators’ current approach to evaluating bank merger proposals is poorly suited for modern financial markets. Policymakers and scholars have traditionally focused on a single issue: whether a bank merger would reduce competition. Over the past two decades, however, changes in bank regulation and market structure—including the repeal of interstate banking restrictions and the emergence of nonbank financial service providers—have rendered bank antitrust analysis largely obsolete. As a result, regulators have rubber-stamped recent bank mergers, despite evidence that such deals could harm consumers and destabilize financial markets

Who\u27s Looking Out for the Banks?

When the Gramm-Leach-Bliley Act authorized financial conglomeration in 1999, Professor Arthur Wilmarth, Jr. presciently predicted that diversified financial holding companies would try to exploit their bank subsidiaries by transferring government subsidies to their nonbank affiliates. To prevent financial conglomerates from taking advantage of their insured depository subsidiaries in this way, policymakers instructed a bank\u27s board of directors to act in the best interests of the bank, rather than the bank\u27s holding company. This symposium Article, written in honor of Professor Wilmarth\u27s retirement, contends that this legal safeguard ignores a critical conflict of interest: the vast majority of large-bank directors also serve as board members of their parent holding companies. These dual directors are therefore poorly situated to exercise the independent judgment necessary to protect a bank from exploitation by its nonbank affiliates. This Article proposes to strengthen bank governance-and better insulate banks from their nonbank affiliates-by mandating that some of a bank\u27s directors be unaffiliated with its holding company. As long as banks are permitted to affiliate with nonbanks, this reform is essential to ensure that someone is looking out for the well-being of insured depository institutions

Open-Source ANSS Quake Monitoring System Software

ANSS stands for the Advanced National Seismic System of the U.S.A., and ANSS Quake Monitoring System (AQMS) is the earthquake management system (EMS) that most of its member regional seismic networks (RSNs) use. AQMS is based on Earthworm, but instead of storing files on disk, it uses a relational database with replication capability to store pick, amplitude, waveform, and event parameters. The replicated database and other features of AQMS make it a fully redundant system. A graphical user interface written in Java, Jiggle, is used to review automatically generated picks and event solutions, relocate events, and recalculate magnitudes. Add‐on mechanisms to produce various postearthquake products such as ShakeMaps and focal mechanisms are available as well. It provides a configurable automatic alarming and notification system. The Pacific Northwest Seismic Network, one of the Tier 1 ANSS RSNs, has modified AQMS to be compatible with a freely available, capable, open‐source database system, PostgreSQL, and is running this version successfully in production. The AQMS Software Working Group has moved the software from a subversion repository server hosted at the California Institute of Technology to a public repository at gitlab.com. The drawback of AQMS as a whole is that it is complex to fully configure and comprehend. Nevertheless, the fact that it is very capable, documented, and now free to use, might make it an attractive EMS choice for many seismic networks

Too Many to Fail: Against Community Bank Deregulation

Since the 2008 financial crisis, policymakers and scholars have fixated on the problem of “too-big-to-fail” banks. This fixation, however, overlooks the historically dominant pattern in banking crises: the contemporaneous failure of many small institutions. We call this blind spot the “too-many-to-fail” problem and document how its neglect has skewed the past decade of financial regulation. In particular, we argue that, for so- called community banks, there has been a pronounced and unjustifiable shift toward deregulation, culminating in sweeping regulatory rollbacks in the Economic Growth, Regulatory Relief, and Consumer Protection Act of 2018. As this Article demonstrates, this deregulatory trend rests on three myths. First, that community banks do not contribute to systemic risk and were not central to the 2008 crisis. Second, that the Dodd-Frank Act imposed regulatory burdens that threaten the survival of the community bank sector. And third, that community banks cannot remain viable without special subsidies or regulatory advantages. While these claims have gained near- universal acceptance among legal scholars and policymakers, none of them withstands scrutiny. Contrary to the conventional wisdom, community banks were key participants in the 2008 crisis, were not uniquely burdened by postcrisis reforms, and continue to thrive economically. Dispelling these myths about the community bank sector leads to the conclusion that diligent oversight of community banks is necessary to preserve financial stability. Accordingly, this Article recommends a reversal of the community bank deregulatory trend and proposes affirmative reforms, including enhanced supervision and macroprudential stress tests, that would help mitigate systemic risks in the community bank sector