Tomonaga–Luttinger Spin Liquid and Kosterlitz–Thouless Transition in the Spin-1/2 Branched Chains: The Study of Topological Phase Transition

In the present work, we provide a comprehensive numerical investigation of the magnetic properties and phase spectra of three types of spin-1/2 branched chains consisting of one, two and three side spins per unit block with intra-chain interaction and a uniform inter-chain interaction in the presence of an external magnetic field. In a specific magnetic field interval, the low-temperature magnetization of these chains shows a step-like behavior with a pronounced plateau depending on the strength and the type of intra-chain interaction being ferromagnetic or antiferromagnetic. We demonstrate that when inter-chain interaction J1 is antiferromagnetic and intra-chain interaction J2 is ferromagnetic, the magnetization of the models manifests a smooth increase without a plateau, which is evidence of the existence of a Luttinger-like spin liquid phase before reaching its saturation value. On the other hand, when J1 is ferromagnetic and J2 is antiferromagnetic, the low-temperature magnetization of the chain with two branches shows an intermediate plateau at one-half of the saturation magnetization that breaks a quantum spin liquid phase into two regions. The magnetization of the chain with three branches exhibits two intermediate plateaus and two regions of a quantum spin liquid. We demonstrate that the chains with more than one side spin illustrate in their ground-state phase diagram a Kosterlitz–Thouless transition from a gapful phase to a gapless spin liquid phase.     

The associations between reflective ability and communication skills among medical students

ObjectivesAssess associations between medical students’ reflective ability demonstrated in written narratives, and communication skills demonstrated later in simulated-patient breaking bad news interactions.MethodsWe analyzed 66 medical students’ reflective ability, using ‘REFLECT’ rubric and four newly developed parameters: Noticing Explanations provided to patients, Noticing Emotions, Remoteness/Connectedness in their writing, and mentioning Self-Emotions. ‘BAS’ and ‘SPIKES’ questionnaires measured students’ communication skills. Spearman and Chi-square tests examined correlations among all variables. Multiple regressions examined associations between reflective ability and demographic variables with communication skills.ResultsSignificant positive correlations between students’ reflective ability, measured by REFLECT and three of the new parameters, and global communication skill scores. Reflective ability of Noticing Explanations in writing was associated with ability to tailoring information to patients’ needs and address emotions.ConclusionsHigh reflective ability may improve communication skills. Specifically, ability to notice explanations to patients may enhance later capability to tailor information to patients and address emotions empathically.Practice implicationsEncourage educational interventions enhancing reflective ability; specifically observation and detailed writing about how explanations are given to patients and patients’ reactions to them. This process may help students develop competency to share and tailor difficult information sensitively—a critical skill when communicating bad news.