Eric Lukosi

• PhD
• Professor (Assistant) at University of Tennessee at Knoxville

Lithium indium diselenide (LISe) is a semiconductor that holds promise for neutron imaging sensor technologies because of its high neutron absorption efficiency and its corresponding ability to discriminate between gamma rays and neutrons. However, being a semiconductor, LISe may not be sufficiently radiation hard for practical application in radia...

Solution grown metal halide perovskites (MHPs) are a class of low-cost, direct conversion semiconducting materials with the potential to meet the need for large areas, high stopping power, and high sensitivity x-ray detectors. While polycrystalline MHP thin films have shown significant potential for meeting this need, their efficiencies for detecti...

Diamond is used as detector material in high energy physics experiments due to its inherent radiation tolerance. The RD42 collaboration has measured the radiation tolerance of chemical vapour deposition (CVD) diamond against proton, pion, and neutron irradiation. Results of this study are summarized in this article. The radiation tolerance of diamo...

Dual γ/neutron radiation sensors are a critical component of the nuclear security mission to prevent the proliferation of a special nuclear material (SNM). While high-performing semiconductors such as high purity germanium (HPGe) and CdZnTe (CZT) already exist in the nuclear security enterprise, their high cost and/or logistical burdens make widesp...

An electronic grade single crystal diamond detector was tested for its chemical and electronic stability after a five day exposure to a 450 °C KCl-LiCl molten salt eutectic. After exposure to the salt, time-of-flight secondary ion mass spectrometry confirmed that lithium diffused into the diamond. However, no degradation of the hole and electron tr...

Diamond is used as detector material in high energy physics experiments due to its inherent radiation tolerance. The RD42 collaboration has measured the radiation tolerance of chemical vapour deposition (CVD) diamond against proton, pion, and neutron irradiation. Results of this study are summarized in this article. The radiation tolerance of diamo...

Several experimental disciplines require simultaneous neutron flux and temperature monitoring. This paper provides the groundwork on a diamond sensor concept that could be used in harsh environments where the limits of current technologies are exceeded. Here, we present initial results on the functionality of a multimodal diamond sensor, which can...

S1. Parametric study of reactive ion etching of diamond 7 To achieve very deep, high aspect ratio DTVs, a parametric study of the etch rate was conducted 8 as a function of chamber pressure, RF power, and inlet composition of the O2/Ar process gases 9 using an Oxford Plasmalab 100 ICP-RIE. The diamond sample was a type Ib, single crystal 10 3.0x3.0...

In this study, a diamond-based neutron scatter camera (DNSC) was developed for neutron spectroscopy in high flux environments. The DNSC was evaluated experimentally and through simulations. It was simulated using several Monte Carlo codes in a two-array layout. The two-array model included two diamond detectors. The simulation reconstructed the spe...

Lithium Indium Diselenide ”LiInSe2” is a semiconducting material considered as a potential option for energy resolved neutron imaging. Its high neutron detection efficiency and excellent spatial resolution make it attractive to be used in the development of a neutron imager for DOE facilities. A neutron imager with an overall enhancement of detecti...

Recently, organometallic halide perovskites (OMHPs) have attracted much interest as a potential medium resolution detector for ionizing radiation sensing applications. Despite moderate success in the development of OMHP radiation detectors to date, efforts to optimize bulk carrier properties are often hindered by device degradation caused by surfac...

Potassium-40 ($^{40}$K) is a long-lived, naturally occurring radioactive isotope. The decay products are prominent backgrounds for many rare event searches, including those involving NaI-based scintillators. $^{40}$K also plays a role in geochronological dating techniques. The branching ratio of the electron capture directly to the ground state of...

We measured the radiation tolerance of commercially available diamonds grown by the Chemical Vapor Deposition process by measuring the charge created by a 120 GeV hadron beam in a 50 μm pitch strip detector fabricated on each diamond sample before and after irradiation. We irradiated one group of samples with 70 MeV protons, a second group of sampl...

Fast neutron imaging is a powerful tool to investigate elemental/isotopic compositions of objects, supporting both scientific studies as well as cargo scanning. Current neutron imaging systems are faced with challenges associated with timing, detection efficiency, and/or spatial resolution. Here, we report on the use of a semiconducting lithium ind...

Correction for ‘Self-assembled nat LiCl–CeCl 3 directionally solidified eutectics for thermal neutron detection’ by Shuangliang Cheng et al. , CrystEngComm , 2020, DOI: 10.1039/c9ce01884k.

The novel natLiCl-CeCl3 eutectic scintillators for thermal neutron detection were synthesized by using the vertical Bridgman method. The eutectic molar ratio of LiCl and CeCl3 is 0.75/0.25. The effects of solidification speed on the microstructure, optical properties, and scintillation properties under  and neutron irradiation were studied. The gr...

Collimation and volumetric studies were done to evaluate the gamma-ray spectroscopic performance of KSr2I5:Eu scintillators grown via the vertical Bridgman method. To demonstrate practical crystal growth for large-scale production, Ø1 in. × 6 in. long crystals were grown using fast pulling rates up to 5 mm/h and short cooling times. The long crysta...

Diamond is a material in use at many nuclear and high energy facilities due to its inherent radiation tolerance and ease of use. We have characterized detectors based on chemical vapor deposition (CVD) diamond before and after proton irradiation. We present preliminary results of the spatial resolution of unirradiated and irradiated CVD diamond str...

Despite the rapid progress in organic–inorganic halide perovskites (OIHPs) for applications such as high-power conversion efficiency solar cells, knowledge of coupling between electronic and ionic charge carrier dynamics is so far limited. While the presence of dual conduction channels is widely accepted, the precise physical mechanisms governing t...

Chemical Vapour Deposition (CVD) diamond is being considered as a material for particle detectors in a harsh radiation environment. This article presents beam test results of 3D pixel detectors fabricated with poly-crystalline CVD diamonds. The cells of the devices had a size of 50 µm×50 µm with columns 2.6 µm in diameter. The cells were ganged in...

We have measured the radiation tolerance of poly-crystalline and single-crystalline diamonds grown by the chemical vapor deposition (CVD) process by measuring the charge collected before and after irradiation in a 50 m pitch strip detector fabricated on each diamond sample. We irradiated one group of sensors with 800 MeV protons, and a second group...

In this work we investigated the effects of replacing some of the matrix iodine atoms in KSr2I5:Eu with bromine, forming new solid solutions of KSr2BrxI(5−x):Eu (where 0.05 ≤ x ≤ 1). Transparent 15 and 22 mm diameter single crystals of KSr2BrxI(5−x):Eu were grown via the vertical Bridgman technique using a two-zone transparent furnace. The scintill...

KSr2I5:Eu 2+ scintillators exhibit better than 3% energy resolution at 662 keV and may be significantly less expensive to produce than other, similar energy resolution scintillators. However, KSr2I5:Eu2+ exhibits a 6.5 Bq/cm³ intrinsic background from the presence of ⁴⁰K. This background is not only the well-known 1.46 MeV gamma, but also the 1.31...

Understanding the impact of environmental gaseous on the surface of organometal halide perovskites (OMHPs) couples to the electronic and ionic transport is critically important. Here, we explore the transport behavior and origins of the gas sensitivity in MAPbBr3 single crystals (SCs) devices using impedance spectroscopy and current relaxation meas...

Understanding the type, formation energy and capture cross section of defects is one of the challenges in the field of organometallic halide perovskite (OMHP) devices. Currently, such understanding is limited, restricting the power conversion efficiencies of OMHPs solar cells from reaching their Shockley-Queisser limit. In more matured semiconducto...

The response of single crystal methylammonium lead tribromide (MAPbBr 3 or MAPB) semiconductors to alpha particles at low voltage is presented. Through analysis of the preamplifier traces induced by ²¹⁰ Po alpha particles and collecting holes, we were able to determine the mobility–lifetime product, apparent mobility, trapping time constant, and th...

Understanding the type, formation energy and capture cross section of defects is one of the challenges in the field of organometallic halide perovskite (OMHP) devices. Currently, such understanding is limited, restricting the power conversion efficiencies of OMHPs solar cells from reaching their Shockley Queisser limit. Here, we report on deep leve...

Organometallic halide perovskite (OMHPs) single crystals have recently gained attention for high-energy radiation detection due to their low trap state densities, high bulk resistivities, excellent stopping power and cost-effective solution growth. An integral focus for radiation sensing materials is reduction of trap states to enhance charge trans...

A scintillating lithium indium diselenide (LISe) single crystal has recently been found to exhibit an eight-fold increase in its apparent light yield within 80 µm across the surface when excited by cold neutrons. The cause of this observation is currently unknown. In this paper, we report on our investigations to explain the previous observations o...

In sight of the luminosity increase of the High Luminosity-LHC (HL-LHC), most experiments at the CERN Large Hadron Collider (LHC) are planning upgrades for their innermost layers in the next 5–10 years. These upgrades will require more radiation tolerant technologies than exist today. Usage of Chemical Vapor Deposition (CVD) diamond as detector mat...

Experimental and computational results of a Δ E /Δ E diamond detection system are presented. The Δ E /Δ E detection system was evaluated using energetic proton and iron beams striking thick polyethylene targets at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL). The measured data for diamond sensor A show good agr...

This paper reports on the charge carrier properties of several lithium indium diselenide (LISe) semiconductors. It was found that the charge collection efficiency of LISe was improved after high flux thermal neutron irradiation including the presence of a typically unobservable alpha peak from hole-only collection. Charge carrier trap energies of t...

Detectors based on Chemical Vapor Deposition (CVD) diamond have been used extensively and successfully in beam conditions/beam loss monitors as the innermost detectors in the highest radiation areas of Large Hadron Collider (LHC) experiments. The startup of the LHC in 2015 brought a new milestone where the first polycrystalline CVD (pCVD) diamond p...

One of the current challenges in methylammonium lead halide (MAPbX3) perovskite application research is understanding contact formation and interfacial phenomena for highly efficient and stable device performance. For semiconductors, development of contact formation is inseparable from device performance and stability. Single‐crystalline MAPbX3 has...

A fabrication technique to create 3D diamond detectors is presented. Deep reactive ion etching was used to create an array of through-diamond vias (TDVs) in a 2 × 2 × 0.15 mm³ electronic grade single crystal diamond detector. The diameter of the TDVs was nominally 30 μm with a pitch of 100 μm between them. The TDVs were filled with chromium using h...

Beam test results of the radiation tolerance study of chemical vapour deposition (CVD) diamond against different particle species and energies is presented. We also present beam test results on the independence of signal size on incident particle rate in charged particle detectors based on un-irradiated and irradiated poly-crystalline CVD diamond o...

The material lithium indium diselenide, a single crystal neutron sensitive semiconductor, has demonstrated its capabilities as a high resolution imaging device. The sensor was prepared with a 55 μ m pitch array of gold contacts, designed to couple with the Timepix imaging ASIC. The resulting device was tested at the High Flux Isotope Reactor, demon...

Potassium-40 (${}^{40}$K) is a background in many rare-event searches and may well play a role in interpreting results from the DAMA dark-matter search. The electron-capture decay of ${}^{40}$K to the ground state of ${}^{40}$Ar has never been measured and contributes an unknown amount of background. The KDK (potassium decay) collaboration will mea...

Potassium-40 (${}^{40}$K) is a background in many rare-event searches and may well play a role in interpreting results from the DAMA dark-matter search. The electron-capture decay of ${}^{40}$K to the ground state of ${}^{40}$Ar has never been measured and contributes an unknown amount of background. The KDK (potassium decay) collaboration will mea...

We report the crystal growth and scintillation properties of two new ternary metal halide scintillators, RbSr2Br5 and RbSr2I5, activated with divalent europium. Transparent 7 mm diameter single crystals with 2.5% Eu²⁺ were grown in evacuated quartz ampoules via the Bridgman technique. RbSr2Br5 and RbSr2I5 have monoclinic crystal structures with den...

Europium doped potassium strontium iodide is a very promising scintillator for national security applications due to its ease of growth and excellent scintillation properties. For this work the fast crystal growth and scintillation properties of 1-inch diameter single crystals of KSr2I5:Eu²⁺ (KSI:Eu) were investigated. We focused our efforts on opt...

This paper presents the computational performance of microfluidic channels (MFCs) within a semiconductor detector to monitor changes in the elemental and isotopic composition of a UOX pressurized water reactor used nuclear fuel dissolved in a KCl/LiCl molten salt. The results indicate that the use of MFC limits alpha energy loss sufficiently enough...

An array of lithium indium diselenide (LISe) scintillators were investigated for application in neutron imaging. The sensors, varying in thickness and surface roughness, were tested using both reflective and anti-reflective mounting to an aluminum window. The spatial resolution of each LISe scintillator was calculated using the knife-edge test and...

This paper reports the deep reactive ion etching of femtosecond laser machined high-aspect graphitic channels through diamond. To begin, two chemical vapor deposition-grown diamond plates, one single-crystal and the other polycrystalline, are processed using the bulk microstructural modification technique of femtosecond-pulsed laser machining. Mult...

Results from detectors of poly-crystalline chemical vapour deposited (pCVD) diamond are presented. These include the first analysis of data of the ATLAS Diamond Beam Monitor (DBM). The DBM module consists of pCVD diamond sensors instrumented with pixellated FE-I4 front-end electronics. Six diamond telescopes, each with three modules, are placed sym...

Lithium indium diselenide, 6LiInSe2 or LISe, is a newly developed neutron detection material that shows both semiconducting and scintillating properties. This paper reports on the performance of scintillating LISe crystals for its potential use as a converter screen for cold neutron imaging. The spatial resolution of LISe, determined using a 10% th...

A current need in nuclear security is an economical, yet high energy resolution (near 2%), scintillation detector suitable for gamma-ray spectroscopy. For current scintillators on the market, there is an inverse relationship between scintillator energy resolution and cost of production. A new promising scintillator, KSr2I5:Eu2+, under development a...

Semiconducting lithium indium diselenide, 6LiInSe2 or LISe, has promising characteristics for neutron detection applications. The 95% isotopic enrichment of 6Li results in a highly efficient thermal neutron-sensitive material. In this study, we report on a proof-of-principle investigation of a semiconducting LISe pixel detector to demonstrate its p...

This paper presents the results of a computational investigation that determined the gamma-ray and neutron response functions of a new semiconducting material, 6LiInSe2, which is very sensitive to thermal neutrons. Both MCNP6 simulations and custom post-processing/simulation techniques were used to determine various detection properties of LISe. Th...

Graphitized columns with ~1 µm diameter through ~500 µm-thick diamonds are formed by femtosecond laser machining using both aberration-corrected and Bessel beam focusing with high numerical aperture for development of radiation-hard, high-energy particle detectors.

(LiInSe2)-Li-6 has gained attention recently as a semiconducting thermal neutron detector. As presented herein, the chalcogenide compound semiconductor also detects incident neutrons via scintillation, making (LiInSe2)-Li-6 the only lithium containing semiconductor to respond to neutrons via both detection mechanisms. Both yellow and red crystals,...

Considering the need for directional sensing at standoff for some security applications and scenarios where a neutron source may be shielded by high Z material that nearly eliminates the source gamma flux, this work focuses on investigating the feasibility of using thermal neutron sensitive boron straw detectors for fast neutron source detection an...

Experimental verification of simulated results of series and parallel diamond detector arrays is reported. Eight commercially available electronic grade single crystal CVD diamond plates were used in series and parallel array configurations and were characterized through alpha particle and neutron exposures. It was found that a series array of diam...

The development of a thermal neutron imaging sensor constructed with semiconducting lithium indium diselenide is presented. Both a computational and experimental investigation were conducted. In the computational investigation, it is shown that the imaging potential of LISe is excellent, even when using a large pixel pitch through the use of super...

Chalcopyrite crystals of 6LiInSe2 have recently been shown to respond to gamma and thermal neutron radiation. Thus far, large crystals have been prepared although the charge collection efficiency has not been sufficient for high energy resolution. In an effort to improve energy resolution needed for gamma spectroscopy as well as pulse shape discrim...

This paper reviews recent efforts in the literature to miniaturize nuclear battery systems. The potential of a nuclear battery for longer shelf-life and higher energy density when compared with other modes of energy storage make them an attractive alternative to investigate. The performance of nuclear batteries is a function of the radioisotope(s),...

A computer-based investigative technique, using the Los Alamos Monte Carlo code MCNP5 version 1.51 (Radiation Safety Information Computational Center), was completed to assess the shallow dose equivalent (SDE) reported on the Landauer, Inc.,e Luxelz optically stimulated light (OSL) dosimeter. Experimental test irradiations were conducted on 18 OSL...

There have been many reports on charged particle and neutron production in LENR experiments but as of yet they have not been correlated in time with excess heat generation. Diamond sensors with palladium electrodes can be utilized to address this need. First results using a diamond sensor are presented.

During the summer of 1991, intense neutron bursts were observed after temperature shocking titanium chips which had been saturated with deuterium gas. The titanium chips were cooled and loaded with deuterium at 77 K and then rapidly heated to 323 K. The rapid heating produces a large pressure increase inside the crystalline lattice of the host meta...

Impurity analysis and compositional distribution studies have been conducted on a crystal of LiInSe2, a compound semiconductor which recently has been shown to respond to ionizing radiation. IR microscopy and laser induced breakdown spectroscopy (LIBS) revealed the presence of inclusions within the crystal lattice. These precipitates were revealed...

During the summer of 1991, intense neutron bursts were observed after temperature shocking titanium chips which had been saturated with deuterium gas. The titanium chips were cooled and loaded with deuterium at 77 K and then rapidly heated to 323 K. The rapid heating produces a large pressure increase inside the crystalline lattice of the host meta...

Since the development of well-established chemical and biological warfare programs by state entities dating from World War I, there has been a growing concern that terrorists and terrorist organizations will start using these agents. The use of chemical and biological agents by terrorists has been documented to occur as far back as 1946; however, t...

The purpose of this paper is to report on the continued work on utilizing a palladium electrode on a diamond sensor in a pressurized hydrogen or deuterium environment to investigate the release of radiation during low energy nuclear reactions (LENR). In this investigation we conducted a long hydrogen exposure to see if palladium electrode delaminat...

There have been many reports on charged particle and neutron production in LENR experiments but as of yet they have not been correlated in time with excess heat generation. Diamond sensors with palladium electrodes can be utilized to address this need. First results using a diamond sensor are presented.

The initial design of a diamond-based neutron spectrometer for fast neutron induced prompt fission neutron spectrum measurements is presented. Initial design investigations have found that coupling a proton radiator to the diamond sensing medium decreases the ultimate neutron energy measurable by a factor of four. The optimum diamond thickness rela...

The use of a thermal neutron detection array comprised of boron straws, a 3He replacement technology, was embedded in a high density polyethylene (HDPE) neutron moderating array to investigate the possibility of one dimensional neutron source localization. The HDPE structure around the boron straw detectors was varied to identify the optimum backgr...

This work discusses the ongoing development of diamond-based radiation sensors for spectrometry within the environments found in low energy nuclear reaction (LENR) experiments. Specifically discussed are the efforts to demonstrate the robustness of palladiumelectrode sensors. This includes fabrication methods, characterization and calibration techn...

In 1991 intense neutron bursts were observed after temperature shocking titanium from LN2 to 100 C that were saturated with deuterium. Counts were time stamped [1] and 2 million neutrons were counted in a five minute period. Rapid heating is suspected to produce a large pressure inside the crystalline lattice.

There have been many reports on charged particle and neutron production in LENR experiments but as of yet they have not been correlated in time with excess heat generation. Diamond sensors with palladium electrodes can be utilized to address this need. First results using a diamond sensor is presented.

The purpose of this paper is to report on the continued work on utilizing a palladium electrode on a diamond sensor in a pressurized hydrogen or deuterium en-vironment to investigate the release of radiation during low energy nuclear reactions (LENR). In this investigation we conducted a long hydrogen exposure to see if palladium electrode delamina...

Monte Carlo simulations have been used for calculating the energy deposition of beta particles in the depletion region of a silicon carbide (SiC) betavoltaic cell along with the corresponding theoretical efficiencies. Three Monte Carlo codes were used in the study: GEANT4, PENELOPE, and MCNPX. These codes were used to examine the transportation of...