New magnetic intermediate state, “<i>B</i>-<i>phase</i>,” in the cubic chiral magnet MnSi

It is well known that the archetype chiral magnet MnSi stabilizes a skyrmion lattice, termed “A-phase,” in narrow temperature range vicinity of paramagnetic boundary around T c ∼ 29 K and H 2 kOe. Recently, it has been predicted at much lower temperatures below , conical helicoid forced ferromagnetic (FFM) states could be separated by new “ unknown state.” In order to detect this state,” we explored phase diagram oriented single crystals as function d.c. magnetic field [Formula: see text] ( T) using a.c. magnetization measurements. For 〈111〉, observed region, “B-phase,” diagram, characterized flat-valley-like anomaly on in-phase component m′), over 3.5 ≤ dc 6.2 kOe just low &lt; 6 K) FFM boundary. The frequency independence 0.3–1000 Hz absence any measurable absorption m″) “B-phase” suggest static nature. was not for either 〈100〉 or 〈110〉, revealing anisotropy play role stabilization phase. compatible with theoretical predictions if state supposedly related relative reorientation four helices MnSi.