Abstract This article centres on Bertha Pappenheim’s translations of Old Yiddish literature, with a particular focus on Die Memoiren der Glückel von Hameln, which was published as a private edition in Vienna in 1910. While the fact that Pappenheim translated Glikl’s Yiddish-language writings into German is well known, little attention has been paid to the particular language of the translated text or to Pappenheim’s techniques of translation more generally. This article delineates Pappenheim’s evolving approach to translation and contextualizes this approach in terms of her feminist and religious commitments. Based on both close and paratextual readings of Die Memoiren der Glückel von Hameln, it identifies a trajectory in Pappenheim’s work from ‘translation proper’ to ‘off-translation’.

This article analyzes Paul Celan's translation of James Baldwin's "Everybody's Protest Novel" and considers the connections between the poetics of these two writers. In addition to their shared preoccupation with and rearticulation of terms such as human, creature, and darkness, the translation reveals how they explored the relationship between literature and reality at early and transitional moments in their careers. While rejecting regnant modes of realism, Baldwin and Celan insisted, in different but related ways, on the bearing of the world on their writing, which they understood as a response to historical catastrophes that resisted inherited categories and hegemonic language. This article demonstrates how reading Baldwin's essay and Celan's translation together can help us understand their peculiar realism anew, and it elucidates how this aspect of their work continues to feel urgent today, with specific reference to the writing of Claudia Rankine.

A condensed phase of zirconium monoxide (ZrO) was detected in YSZ (Zr0.92Y0.08O2-delta) coatings deposited using plasma spray-physical vapor deposition. The rapid cooling rate of this process can result in the condensation of nonequilibrium states that can be kinetically trapped in the coatings. The columnar microstructure contained a mixture of YSZ, ZrO2, and ZrO phases. The ZrO phase was expected to be conductive based on density functional theory calculations, and preliminary impedance measurements were performed that supported this prediction. When heated in an oxygen-containing environment, the ZrO phase remains in the coating until similar to 450 K, at which point it disappears quickly, as confirmed by X-ray diffraction and thermogravimetric methods. The loss of ZrO in the coating was also linked to a loss in electrical conductivity. However, it was shown that this phase can persist at elevated temperatures of similar to 1000 K in vacuum or inert environments for at least 100 h.

MIT LL and CURT MGH are developing a novel laser system that acquires ultrasound (US) images from human tissue without patient contact. The system is termed, noncontact laser ultrasound (NCLUS). NCLUS employs a pulsed laser that converts optical energy to US waves at the skin surface via thermoelastic mechanisms. A laser Doppler vibrometer then measures emerging US waves from the tissue interior arriving at the skin surface. NCLUS has potential to advance medical US by overcoming limitations of a contact US probe. Due to its noncontact nature, NCLUS is intended to 1) mitigate operator variability, 2) provide a fixed reference for comparing repeat scans over time, 3) fully automate US image data acquisition, reducing the need for a sonographer, and 4) transmit US in any “array” locations desired. NCLUS can deliver a wide range of array compositions that yield great versatility in acoustic beam shaping and steering in tissue. NCLUS is designed with the goal for multiple applications: anatomical imaging, bone elastography, disease feature tracking, US acquisition through burned or traumatized tissue, neck injuries, open surgical regions, neonatal care, and so forth. We are currently transitioning the NCLUS development from a proof-of-concept system to a risk reduction prototype to determine if NCLUS has a path to meet the requirements of a clinically relevant system.

The time-domain thermoreflectance metrology is applied to evaluate the thermal conductivities of filler particles embedded in a composite matrix. Specifically, a system of glass and ceramic microspheres with a diameter of 100 to 150 μm embedded in an epoxy matrix was used as a representation of a typical composite thermal interface material (TIM) suitable for microelectronics applications. These measurements provide a direct characterization of the thermal properties of filler materials. The measured thermal conductivities of both borosilicate glass and yttria stabilized zirconia microspheres agree well with literature values for bulk materials, whereas the thermal conductivity of the alumina microspheres is nearly 50% lower than that of bulk crystals. The reduction in thermal conductivity of the alumina microspheres highlights how important this level of understanding is for TIM development and is attributed to enhanced phonon scattering due to structural heterogeneity, such as defects induced by phase mixing and microvoids. Combining sample preparation, structural characterization, and direct thermal measurements, our study reveals the structure–thermal property relationship for individual microspheres. The results of this work can facilitate the design and engineering of composite-based thermally conductive materials for thermal management applications.

Thin films of In2O3 and Fe2O3 have been deposited on (001) MgO using pulsed-laser deposition (PLD). These thin-film diffusion couples were then reacted in an applied electric field at elevated temperatures. In this type of solid-state reaction, both the reaction rate and the interfacial stability are affected by the transport properties of the reacting ions. The electric field provides a very large external driving force that influences the diffusion of the cations in the constitutive layers. This induced ionic current causes changes in the reaction rates, interfacial stability and distribution of the phases. Through the use of electron microscopy techniques the reaction kinetics and interface morphology have been investigated in these spinel-forming systems, to gain a better understanding of the influence of an electric field on solid-state reactions.

Coupled semiconductor laser arrays are naturally non-Hermitian optical systems. We show that in a weakly coupled semiconductor laser array, the control for gain/loss is dominated by the nonlinearities, rather than simply following the pump profile.

Optically-coupled semiconductor laser arrays are described by coupled rate equations. The coupled mode equations and carrier densities are included in the analysis, which inherently incorporate the carrier-induced nonlinearities including spatial hole burning and amplitude-phase coupling. We solve the steady-state coupled rate equations and consider the cavity frequency detuning and the individual laser pump rates as the experimentally controlled variables. We show that the carrier-induced nonlinearities play a critical role in the mode control, and we identify gain contrast induced by cavity frequency detuning as a unique mechanism for mode control. Photon-mediated energy transfer between cavities is also discussed. Parity-time symmetry and exceptional points in this system are studied. Unbroken parity-time symmetry can be achieved by judiciously combining cavity detuning and unequal pump rates, while broken symmetry lies on the boundary of the optical locking region. Exceptional points are identified at the intersection between broken and unbroken parity-time symmetry.

A grain-selection template was applied to freeze casting to control nucleation of pore-forming crystals and achieve ceramics with highly aligned pore structures. A polymethylsiloxane preceramic polymer was freeze cast with cyclohexane as a solvent to produce dendritic pores in SiOC. Image analysis and permeability measurements were performed to quantify the influence of various templates on sample properties. Results show that the percentage of porosity aligned along the freezing axis increased from 13.9% without a template to 92.6% with an optimal template. The Darcian permeability constant increased by more than 6-fold, from 3.4 × 10− 12 to 2.1 × 10− 11 m2.

We show that optical coupling can be achieved reproducibly and with high yield by resonance tuning the elements of substrate-emitting and top-emitting vertical-cavity surface-emitting laser arrays. The resonance tuning is enabled by electrical isolation of the lasing elements in the array, which in this paper is done by post fabrication processing. Prior to electrical isolation, the laser arrays exhibit incoherent optical properties. Using resonance tuning, both in-phase and out-of-phase coherent modes are observed.

We demonstrate that photonic crystal anti-guided VCSEL arrays can be tuned to coherent operation by control of the cavity resonance by independent control of the bias currents.

Vertical-cavity surface-emitting laser arrays can be designed to operate in a coherently coupled mode, however, high yield has been challenging in past efforts. We discuss microcavity laser arrays that are designed to be optically coupled but with independent bias current injection into each array element. We demonstrate that these arrays can be electronically tuned to coherently coupled operation and at bias conditions not previously realized. Control of injection bias conditions to individual array elements allows resonance tuning of each element with the result that the phase relation and coherence of the array can be engineered. This control enables increased output power in either in-phase or out-of-phase coherent operation from a single array, and ensures coherent operation from nearly all arrays. This ability to tune into coherence will enhance the performance of phased vertical cavity laser arrays as well as improve their fabrication yield.

Two-dimensional coherently coupled photonic crystal ion-implanted bottom emitting vertical cavity surface emitting laser arrays are demonstrated. Subthreshold luminescence shows uniform current injection below threshold, benefiting from the improved contact alignment compared with the top emitting arrays. In-phase operation has been achieved in 2x2 and 3x3 arrays at lasing threshold. A remaining challenge is achieving uniform current distribution above lasing threshold for larger arrays due to the variation of series resistance through each of the elements of the arrays.

Vertical-cavity surface-emitting laser arrays can be designed to operate in a coherently coupled mode, however, high yield has been challenging in past efforts. We discuss microcavity laser arrays that are designed to be optically coupled but with independent bias current injection into each array element. We demonstrate that these arrays can be electronically tuned to coherently coupled operation and at bias conditions not previously realized. Control of injection bias conditions to individual array elements allows resonance tuning of each element with the result that the phase relation and coherence of the array can be engineered. This control enables increased output power in either in-phase or out-of-phase coherent operation from a single array, and ensures coherent operation from nearly all arrays. This ability to tune into coherence will enhance the performance of phased vertical cavity laser arrays as well as improve their fabrication yield.

We show a significant improvement of modulation bandwidth from $2\times 1$ photonic crystal vertical-cavity surface-emitting laser arrays. Control of injection bias conditions to array elements enables resonance tuning of each element with variation of the phase relation and coherence of the array, resulting in the ability to tailor the modulation response. A bandwidth of 37 GHz is obtained under highly single-mode coherent operation with narrow spectral width and increased output power while the laser array is biased at low current density. Lasers with such performance characteristics may greatly enhance high-rate data transfer in computer server, data center, and supercomputer applications with potentially long device lifetime.

Phased arrays of microcavity lasers exhibit novel optical properties as well as application as electronic beam steering and high brightness sources. The coherence and beam divergence of vertical cavity surface emitting laser (VCSEL) arrays are both related to the relative phase between the array elements, which in turn can be controlled by bias current. We have recently demonstrated that phased VCSEL arrays rely on a fundamentally different phase-shifting mechanism arising from temporal coherence [1]. Here we report the ability to tune virtually any array to coherence by insuring spectral overlap between the resonance of each element of the array. A 2x1 phased VCSEL array is shown in Fig. 1 [2]. The coherent laterally coupled array is fabricated by combining a photonic crystal etched hole pattern with an ion implant-defined laser gain structure. The photonic crystal provides stable index guiding for array elements and greater optical loss for higher order modes [3]. This structure enables strong coupling between array elements and simultaneously enables independent current injection into either cavity. Shown in Fig. 2 is the spatially resolved emission wavelength from the array and the far-field profile as a function of injection current. By preferential current injection to one element with respect to the other, we change the cavity refractive index for that element through ohmic heating and electronic suppression [2], thus varying its natural resonance, as confirmed by spatially resolved spectra measurements in Fig. 2(a). In effect, by varying the bias we can tune the resonance of each element as well as the phase relation and coherence of the array. For the array in Fig. 1, by electrically tuning elements 1 and 2, we obtain highly single-mode emission with an “out-of-phase” far-field mode throughout the coherent operation regime 2. With sufficient detuning two clearly defined spectral peaks with a single broad Gaussian far-field are apparent when Elements 1 and 2 become uncoupled and incoherent.

In this paper, we show that independent current injection into phased photonic crystal VCSEL arrays can drive the arrays to exhibit either coherent or incoherent operation. For the single mode coherent operation, 25 GHz small signal modulation is obtained.

We demonstrate 2-dimentional coherently coupled bottom-emitting VCSEL arrays. In-phase operation has been obtained from 3-element triangular arrays, while out-of-phase operation has been obtained from 2×2, 3×3, and 4×4 arrays.